Calculating sample sizes for cluster randomized trials: we can keep it simple and efficient!

A hybrid approach to sample size re-estimation in cluster randomized trials with continuous outcomes

This study presents a hybrid (Bayesian-frequentist) approach to sample size re-estimation (SSRE) for cluster randomised trials with continuous outcome data, allowing for uncertainty in the intra-cluster correlation (ICC). In the hybrid framework, pre-trial knowledge about the ICC is captured by placing a Truncated Normal prior on it, which is then updated at an interim analysis using the study data, and used in expected power control. On average, both the hybrid and frequentist approaches mitigate against the implications of misspecifying the ICC at the trial's design stage. In addition, both frameworks lead to SSRE designs with approximate control of the type I error-rate at the desired level. It is clearly demonstrated how the hybrid approach is able to reduce the high variability in the re-estimated sample size observed within the frequentist framework, based on the informativeness of the prior. However, misspecification of a highly informative prior can cause significant power loss. In conclusion, a hybrid approach could offer advantages to cluster randomised trials using SSRE. Specifically, when there is available data or expert opinion to help guide the choice of prior for the ICC, the hybrid approach can reduce the variance of the re-estimated required sample size compared to a frequentist approach. As SSRE is unlikely to be employed when there is substantial amounts of such data available (ie, when a constructed prior is highly informative), the greatest utility of a hybrid approach to SSRE likely lies when there is low-quality evidence available to guide the choice of prior.

Impact of a community health worker led intervention for improved blood pressure control in urban Nepal: an open-label cluster randomised controlled trial

Background

Effective control of hypertension remains challenging in low and middle-income countries. We tested the effectiveness of comprehensive approaches to hypertension management including six home visits by community health workers with regular follow up by a trained healthcare provider on blood pressure levels in Nepal.

Methods

We implemented a non-blinded, open-label, parallel-group, two-arm cluster randomised controlled trial, with 1:1 allocation ratio in Budhanilakantha municipality, Kathmandu, Nepal. Ten public health facilities and their catchment area were randomly allocated to receive comprehensive intervention or only usual hypertension care. We recruited 1252 individuals aged 18 years and older with hypertension. The primary outcome was systolic blood pressure. Secondary outcomes were diastolic blood pressure, proportion with controlled blood pressure, waist to hip ratio, body mass index, physical activity, diet quality score, daily salt intake, adherence to antihypertensives, hypertension knowledge and perceived social support. Primary analysis was by intention-to-treat using a linear mixed model.

Findings

Participants were, on average 57 years old, 60% females, 84% married, 54% Brahmin/Chettri ethnicity and 33% were illiterate. The decrease in mean systolic blood pressure (1.7 mm Hg, 95% CI -0.1, 3.4) and diastolic blood pressure (1.6 mm Hg, 95% CI 0.5, 2.6) was more in the intervention arm compared to the control. The proportion with blood pressure control (OR 1.5 95% CI 1.0, 2.1) and engaging in adequate physical activity (≥600 Metabolic equivalents of task per week) (OR 2.2, 95% CI 1.6, 3.1) were higher in the intervention arm compared to control. The change in hypertension knowledge score was higher and daily salt intake was lower in the intervention arm compared to control. Waist to hip ratio increased more and global dietary requirement scores decreased more in the intervention group and there was no effect on the body mass index and adherence to antihypertensives.

Interpretation

Community health workers facilitated home support and routine follow-up care by healthcare providers was effective in controlling blood pressure in urban Nepal. These findings suggest comprehensive interventions targeting individual, community and health system barriers are feasible in low resource settings, but larger implementation trials are needed to inform future scale-up.

Funding

This work was supported by Norwegian University of Science and Technology, Trondheim, Norway (Project number 981023100).

Effectiveness of the 'SELF-program' on nurses' activity encouragement behavior and nursing home resident's ADL self-reliance; a cluster-randomized trial

BACKGROUND

Nurses play a crucial role in encouraging nursing home resident's activity and independent functioning. However, nurses often take over tasks unnecessarily, which can deprive resident's remaining abilities. The Function-Focused Care philosophy offers guidance for developing programs that support nurses to optimize activity and independence of older people. However, such programs developed internationally have demonstrated inconsistent effects. Lessons have been gathered to improve future programs, which led to the development of the 'SELF-program': a holistic, interactive and theory-based program that aims to improve activity encouragement behavior of nurses and indirectly to optimize self-reliance of nursing home residents.

OBJECTIVE

The aim of this study was to examine the effectiveness of the SELF-program on nurses' activity encouragement behavior and nursing home residents' self-reliance in activities of daily living.

METHOD

The program's effectiveness was examined in a two-arm (SELF-program vs Care as Usual) cluster-randomized trial in Dutch nursing homes. Wards were recruited as units of intervention. The MAINtAIN questionnaire was used to assess the primary outcome: nurses' activity encouragement behavior regarding self-reliance in activities of daily living. The GARS-4 questionnaire was used to assess the secondary outcome: residents' self-reliance in activities of daily living. Measurements were taken at: 1) baseline, 2) three months after baseline, and 3) six months (for residents) and nine months (for nurses) after baseline. The acquired data was analyzed using mixed linear regression. Both adjusted and unadjusted analyses are reported.

RESULTS

Twenty-eight nursing home wards, with 287 nurses and 241 residents participated in the study. A statistically significant treatment by time interaction effect was observed in nurses' activity encouragement behavior at three months (d = 0.53; p = .003; 95 % CI 1.88-8.02) and at nine months (d = 0.38; p = .02; 95 % CI 0.67-7.27). No statistically significant treatment by time interaction effects were observed in residents' self-reliance in activities of daily living. However, a trend was observed towards a less pronounced decrease in self-reliance in those residents allocated to wards that exposed nurses to the SELF-program, reflected by small to medium negative effect sizes at three months (d = -0.25; p = .07; 95 % CI -2.21 - 0.09) and at six months (d = -0.29; p = .07; 95 % CI -3.22 - 0.11).

CONCLUSION

The SELF-program was effective in improving nurses' activity encouragement behavior. The process evaluation conducted parallel to the trial could yield valuable lessons to further improve the SELF-program before widespread implementation.

TRIAL-REGISTRATION

The study is registered in the Dutch Trial Register (NL9189), as of December 22 2020. Recruitment commenced in March 2021.

Exposure patterns and the risk factors of Crimean Congo hemorrhagic fever virus amongst humans, livestock and selected wild animals at the human/livestock/wildlife interface in Isiolo County, upper eastern Kenya

Crimean Congo hemorrhagic fever (CCHF) is a tick-borne zoonotic disease caused by CCHF virus (CCHFV). The disease has a complex transmission cycle that involves a wide range of hosts including mammalian and some species of birds. We implemented a sero-epidemiological study in Isiolo County, Kenya, to determine relative seroprevalences of CCHFV in humans, livestock and in wild animals. In addition, we identified subject and environment level factors that could promote exposure to CCHFV. Humans (n = 580) and livestock (n = 2,137) were recruited into the study through a multistage random sampling technique, and in addition, various species of wild animals (n = 87) were also sampled conveniently. Serum samples from all recruited humans and animals were collected and screened for CCHFV antibodies using ID Screen multispecies, double-antigen IgG enzyme-linked immunosorbent assay (ELISA). The overall anti-CCHFV IgG seroprevalences in humans, cattle, goats, sheep and camels were 7.2% [95% CI: 3.1-15.8%], 53.9% [95% CI: 30.7-50.9%], 11.6% [95% CI: 7.2-22.5%], 8.6% [95% CI: 3-14%] and 89.7% [95% CI: 78-94%], respectively. On average, the sampled wild animals had CCHFV seroprevalence of 41.0% [95% CI: 29.1-49.4%]; giraffes had the highest mean CCHF seroprevalence followed by buffaloes, while impala had very low exposure levels. Statistical analyses using mixed effects logistic regression models showed that CCHFV exposure in humans was significantly associated with male gender, being over 30 years of age and belonging to a household with a seropositive herd. In livestock, a combination of animal- and environment level factors including older animals, being in an area with high normalized difference vegetation index (NDVI) and high vapour pressure deficit were significantly associated with CCHFV infection. Age, sex and species of wild animals were considered as the key risk factors in the analysis, but none of these variables was significant (P-value = 0.891, 0.401 and 0.664, respectively). Additionally, RT-qPCR analysis revealed the presence of CCHFV RNA in camels (30%), cattle (14.3%), and goats (3.8%), but not in humans, sheep, or wild animals. This study demonstrates that environmental factors, such as NDVI and vapor pressure deficit, affect CCHFV exposure in livestock, while the presence of infected livestock is the key determinant of human exposure at the household level. These findings underscore the importance of using One Health approaches to control the disease in human-livestock-wildlife interfaces. For instance, the existing CCHF surveillance measures could be enhanced by incorporating algorithms that simulate disease risk based on the environmental factors identified in the study. Additionally, tick control in livestock, such as the use of acaricides, could reduce CCHFV exposure in livestock and, consequently, in humans.

The symbolic two-step method applied to cancer care delivery research: Safeguarding against designing an underpowered cluster randomized trial with a continuous outcome by accounting for the imprecision in the within- and between-center variation

BACKGROUND

Knowing the predictive factors of the variation in a center-level continuous outcome of interest is valuable in the design and analysis of parallel-arm cluster randomized trials. The symbolic two-step method for sample size planning that we present incorporates this knowledge while simultaneously accounting for patient-level characteristics. Our approach is illustrated through application to cluster randomized trials in cancer care delivery research. The required number of centers (clusters) depends on the between- and within-center variance; the within-center variance is a function of estimates obtained by regressing the log within-center variance on predictive factors. Obtaining accurate estimates of the components needed to characterize the within-center variation is challenging.

METHODS

Using our previously derived sample size formula, our objective in the current research is to directly account for the imprecision in these estimates, using a Bayesian approach, to safeguard against designing an underpowered study when using the symbolic two-step method. Using estimates of the required components, including the number of centers that contribute to those estimates, we make formal allowance for the imprecision in these estimates on which a sample size will be based.

RESULTS

The mean of the distribution for power is consistently smaller than the single point estimate that the sample size formula yields. The reduction in power is more pronounced in the presence of increased uncertainty about the estimates with the reduction becoming more attenuated with increased numbers of centers that contribute to the estimates.

CONCLUSIONS

Accounting for imprecision in the estimates of the components required for sample size estimation using the symbolic two-step method in the design of a cluster randomized trial yields conservative estimates of power.

A Hybrid Pragmatic and Factorial Cluster Randomized Controlled Trial for an Anti-racist, Multilevel Intervention to Improve Mental Health Equity in High Schools

Systemic racism is pervasive in US society and disproportionately limits opportunities for education, work, and health for historically marginalized and minoritized racial and ethnic groups, making it an urgent issue of social justice. Because systemic racism is a social determinant of health prevalent across multiple social and institutional structures, it requires multilevel intervention approaches using effective designs and analytic methods to measure and evaluate outcomes. Racism is a fundamental cause of poor health outcomes, including mental health outcomes; thus, mental health services and programs that address racism and discrimination are key to promoting positive mental health of racial and ethnic minority youth. While multilevel interventions are well-suited for improving outcomes like youth mental health disparities, their evaluation poses unique methodological challenges, requiring specialized design and analytic approaches. There has been limited methodological guidance provided to researchers on how to test multilevel interventions using approaches that balance methodological rigor, practicality, and acceptability across stakeholder groups, especially within communities most affected by systemic racism. This paper addresses this gap by providing an example of how to rigorously evaluate a hypothetical, theoretically based, multilevel intervention promoting mental health equity in three US school systems using an anti-racist approach intervening at the macro- (i.e., school system), meso- (i.e., school), and micro- (i.e., family and student) levels to improve mental health in adolescents. We describe the design, sample size considerations, and analytic methods to comprehensively evaluate its effectiveness while exploring the extent to which the components interact synergistically to improve outcomes. The methodological approach proposed can be adapted to other multilevel interventions that include strategies addressing macro-, meso-, and micro-levels of influence.

Embedded motivational interviewing combined with a smartphone application to increase physical activity in people with sub-acute low back pain: a cluster randomised controlled trial

BACKGROUND

Moderately vigorous physical activity (PA) may be beneficial for people with sub-acute low back pain (LBP), but may initially be painful for patients and challenging for physical therapists to facilitate.

OBJECTIVES

This study investigated motivational interviewing (MI) delivered by physical therapists and a smartphone app for increasing PA in people with LBP.

METHODS

A mixed methods cluster randomised controlled trial involving 46 adults with LBP in Melbourne, Australia. Participants attended weekly 30-min physical therapy consultations for 6 weeks. Experimental group physical therapists were taught to embed MI into consultations and patients were provided with a self-directed app. The primary outcome was accelerometer-derived moderately vigorous PA. Secondary outcomes were LBP disability (Oswestry Disability Index), functional capacity (Patient Specific Functional Scale), and self-efficacy (Pain Self-Efficacy Questionnaire). Between-group differences were analysed by ANCOVA post-intervention.

RESULTS

There was no statistically significant difference between the experimental group and control group for PA. Between-group differences in LBP disability (MD= 19.4 units, 95% CI: 8.5, 30.3), functional capacity (primary MD= -4.1 units, 95% CI: -6.9, -1.3; average MD= -3.1, 95% CI: -4.9, -1.2) and self-efficacy (MD -11.3 units, 95%CI -20.2, -2.5) favoured the control group with small to moderate effect sizes. There were low levels of overall engagement with the app.

CONCLUSION

The embedded MI intervention was no more beneficial than physical therapy alone for PA and was associated with poorer LBP disability, function, and self-efficacy. The effectiveness of embedding MI and a smartphone app into usual care for LBP was not supported.

Goal-Directed Treatment of Patients With Anxiety and Mood Disorders in a Regular Curative Mental Health Care Setting

This study examined whether goal-directed treatment leads to improved treatment outcomes for patients with a primary mood or anxiety disorder and whether beneficial outcomes are achieved sooner compared to treatment as usual. In a quasi-experimental controlled study with a nested design, 17 therapists received training in goal-directed treatment and treated 105 patients with anxiety or mood disorders using principles of goal-directed treatment. Treatment results on a generic self-report instrument were compared with two control groups: a historical control group consisting of 16 of the 17 participating therapists, who provided treatment as usual to 97 patients before having received training in goal-directed treatment, and a parallel control group consisting of various therapists, who provided treatment as usual to 105 patients. Symptom reduction on a self-report measure was compared using multilevel analysis. A survival analysis was performed to assess whether a satisfactory end state had been reached sooner after goal-directed treatment. The results of this study show that goal-directed treatment only led to a significantly better overall treatment outcome compared to the parallel treatment as usual group. Furthermore, goal-directed treatment was significantly shorter than both treatment as usual groups. In conclusion, this research suggest that goal-directed treatment led to a similar or better treatment outcome in a shorter amount of time.

Cluster Randomized Trials with a Pretest and Posttest: Equivalence of Three-, Two- and One-Level Analyses, and Sample Size Calculation

In a cluster randomized trial clusters of persons, for instance, schools or health centers, are assigned to treatments, and all persons in the same cluster get the same treatment. Although less powerful than individual randomization, cluster randomization is a good alternative if individual randomization is impossible or leads to severe treatment contamination (carry-over). Focusing on cluster randomized trials with a pretest and post-test of a quantitative outcome, this paper shows the equivalence of four methods of analysis: a three-level mixed (multilevel) regression for repeated measures with as levels cluster, person, and time, and allowing for unstructured between-cluster and within-cluster covariance matrices; a two-level mixed regression with as levels cluster and person, using change from baseline as outcome; a two-level mixed regression with as levels cluster and time, using cluster means as data; a one-level analysis of cluster means of change from baseline. Subsequently, similar equivalences are shown between a constrained mixed model and methods using the pretest as covariate. All methods are also compared on a cluster randomized trial on mental health in children. From these equivalences follows a simple method to calculate the sample size for a cluster randomized trial with baseline measurement, which is demonstrated step-by-step.

A web-enabled, school-based intervention for bullying prevention (LINKlusive): a cluster randomised trial

Background

There is a need for more sustainable interventions and for assessing the effectiveness of school-based universal anti-bullying programmes in vulnerable populations. We assessed the efficacy of a multicomponent, web-enabled, school-based intervention that aims to improve school climate and reduce bullying (LINKlusive) relative to conventional practices (control condition).

Methods

We conducted a cluster randomised controlled trial in primary and secondary schools in Madrid, Spain. The primary outcome measure was peer-reported bullying victimisation after the 12-week intervention (study endpoint). We analysed data using longitudinal mixed-effects models. The trial was registered with the ISRCTN registry (15719015).

Findings

We included 20 schools (10 in each group); 6542 students participated at baseline; 6403 were assessed at study endpoint. After the intervention, there was a statistically significant reduction in bullying victimisation in both the intervention (OR 0.61, 95% CI [0.41, 0.90]) and control groups (OR 0.69, 95% CI [0.51, 0.92]), with no evidence of differences in the whole sample (OR 0.89, 95% CI [0.58, 1.36]; aOR 0.89, 95% CI [0.58, 1.37]). Subgroup analyses showed a statistically significant effect of LINKlusive on bullying victimisation in primary education (aOR 0.68, 95% CI [0.47, 0.98]). In students with peer-reported bullying victimisation at baseline, LINKlusive showed a statistically significant effect on depression (-1.43, 95% CI [-2.46, -0.40], adjusted standardised mean difference (SMD) -0.41) and quality of life (2.18, 95% CI [0.80, 3.56], adjusted SMD 0.45).

Interpretation

LINKlusive could be effective in reducing bullying victimisation in primary school students. Sustainable whole-school interventions to promote mental health and reduce risk factors are warranted to improve outcomes in young people, especially in the early years of education.

Funding

Instituto de Salud Carlos III, Spanish Ministry of Science and Innovation.

Correlates of supportive care needs among Asian Americans with colorectal, liver, or lung cancer from a web-based patient navigation portal intervention: The Patient COUNTS study

BACKGROUND

Cancer is the leading cause of death among Asian Americans, who often face barriers to cancer care. Cancer supportive care needs among Asian Americans remain understudied.

AIMS

We examined cancer supportive care needs and participant factors correlated with these needs, identified profiles of supportive care needs, and examined whether needs profiles are associated with quality of life among Asian American adults.

METHODS AND RESULTS

We recruited 47 Asian American adults with colorectal, liver, or lung cancer who spoke Chinese, English, or Vietnamese, and were starting or undergoing cancer treatment. We assessed cancer supportive care needs in four domains: cancer information, daily living, behavioral health, and language assistance. Hierarchical cluster analysis was used to identify clusters of participants based on their supportive need profiles to further examine the association between need profiles and quality of life (QoL) assessed by the Functional Assessment of Cancer Therapy. Participants (mean age = 57.6) included 72% males and 62% spoke English less than very well. Older participants (age ≥ 65) and those with annual income <$50K reported higher daily living needs. Men and younger participants (age < 50) reported higher behavioral health needs. We found three clusters displaying distinct cancer supportive need profiles: Cluster 1 (28% of the sample) displayed high needs across all domains; Cluster 2 (51%) had low needs across all domains; and Cluster 3 (21%) had high needs for cancer information and daily living. Cluster 1 participants reported the lowest QoL.

CONCLUSION

Cancer supportive care needs among Asian American patients with colorectal, liver, and lung cancer were associated with patient characteristics and QoL. Understanding cancer supportive care needs will inform future interventions to improve care and QoL for Asian American patients with cancer.

CLINICALTRIALS

gov Identifier: NCT03867916.

Bayesian optimal stepped wedge design

Recently, there has been a growing interest in designing cluster trials using stepped wedge design (SWD). An SWD is a type of cluster-crossover design in which clusters of individuals are randomized unidirectional from a control to an intervention at certain time points. The intraclass correlation coefficient (ICC) that measures the dependency of subject within a cluster plays an important role in design and analysis of stepped wedge trials. In this paper, we discuss a Bayesian approach to address the dependency of SWD on the ICC and robust Bayesian SWDs are proposed. Bayesian design is shown to be more robust against the misspecification of the parameter values compared to the locally optimal design. Designs are obtained for the various choices of priors assigned to the ICC. A detailed sensitivity analysis is performed to assess the robustness of proposed optimal designs. The power superiority of Bayesian design against the commonly used balanced design is demonstrated numerically using hypothetical as well as real scenarios.

Peer-led training improves lifejacket wear among occupational boaters: Evidence from a cluster randomized controlled trial on Lake Albert, Uganda

BACKGROUND

The burden of drowning among occupational boaters in low and middle-income countries is highest globally. In Uganda, over 95% of people who drowned from boating-related activities were not wearing lifejackets at the time of the incident. We implemented and evaluated a peer-led training program to improve lifejacket wear among occupational boaters on Lake Albert, Uganda.

METHODS

We conducted a two-arm cluster randomized controlled trial in which fourteen landing sites were randomized to the intervention and non-intervention arm with a 1:1 allocation ratio. In the intervention arm, a six-month peer-to-peer training program on lifejacket wear was implemented while the non-intervention arm continued to receive the routine Marine Police sensitizations on drowning prevention through its community policing program. The effect of the intervention was assessed on self-reported and observed lifejacket wear using a test of differences in proportions of wear following the intention to treat principle. The effect of contamination was assessed using mixed effect modified Poisson regression following the As Treated analysis principle at 95% CI. Results are reported according to the CONSORT statement-extension for cluster randomized trials.

RESULTS

Self-reported lifejacket wear increased markedly from 30.8% to 65.1% in the intervention arm compared to the non-intervention arm which rose from 29.9% to 43.2%. Observed wear increased from 1.0% to 26.8% in the intervention arm and from 0.6% to 8.8% in the non-intervention arm. The test of differences in proportions of self-reported lifejacket wear (65.1%- 43.2% = 21.9%, p-value <0.001) and observed wear (26.8%- 8.8% = 18%, p-value <0.001) showed statistically significant differences between the intervention and non-intervention arm. Self-reported lifejacket wear was higher among boaters who received peer training than those who did not (Adj. PR 1.78, 95% CI 1.38-2.30).

CONCLUSION

This study demonstrated that peer-led training significantly improves lifejacket wear among occupational boaters. The government of Uganda through the relevant ministries, and the Landing Site Management Committees should embrace and scale up peer-led training programs on lifejacket wear to reduce drowning deaths.

Effect evaluation of a comprehensive sexuality education intervention based on socio-emotional learning among adolescents in Jakarta, Indonesia

Introduction

The field of comprehensive sexuality education (CSE) has switched from a focus on adolescents’ health to a more holistic approach, embracing the concept of sexual development with the aim of improving adolescents’ sexual well-being. The growing interest in the link between CSE and socio-emotional learning (SEL) competencies led to the development of the Journey4Life (J4L), a comprehensive sexuality education curriculum based on socio-emotional learning. In the current research, we evaluate the effectiveness of this program on perceived behavioral control, gender equality attitudes, norms, and intentions related to sexual and reproductive health and rights.

Methods

To this end, we conducted a Cluster Randomized Trial among 14 senior secondary schools in Jakarta, Indonesia. A questionnaire was administered before and after implementation of the J4L program among 16–17 year old pupils; n = 906 completed baseline measurement, n = 771 completed endline measurement. With a final matched sample of N = 466 (65.5% girls) we conducted a mixed model repeated measures ANOVA.

Results

Unfortunately, only limited and inconsistent results were found. We found that at endline, girls had stronger positive gender equality attitudes than boys; that overall attitudes towards reporting sexual violence were stronger for girls than for boys. However, contrary to our expectations, respondents had more positive attitudes toward child marriage at baseline than at endline.

Discussion

Inconsistency and non-statistical significance of results limit our ability to draw firm conclusions about the effectiveness of the Journey4Life. We discuss how complex comprehensive sexuality education interventions could best be evaluated, since our study highlights the need for better conceptualization, operationalization and measurement of the interconnection between comprehensive sexuality education and socio-emotional learning.

Decreasing consumption of sugar-sweetened beverages and Raising tap water consumption through Interventions based on Nutrition and sustainability for Kids: study protocol of the "DRINK" cluster randomised controlled trial

BACKGROUND

Effectiveness of actions to reduce sugar-sweetened beverage (SB) consumption in children still needs to be improved. Furthermore, the growing concern about sustainable food systems encourages to develop sustainability-based interventions. The objective of this cluster randomised controlled trial is to evaluate the long-term effectiveness of nutrition- and environmental sustainability-based interventions on the reduction in SB intake and on the increase in tap water consumption in 3rd to 6th grade primary school children (8 to 11 years of age).

METHODS

Forty-eight French-speaking Belgian primary schools (equivalent to around 3500 pupils involved in the evaluation) are randomised using a factorial plan: (i) control, (ii) nutrition-based intervention, (iii) sustainability-based intervention, and (iv) both. The interventions (encouragement of water breaks; provision of posters, leaflets, reusable cups, and glass bottles; website; meetings at school) were undertaken from February 2022 to June 2023. Evaluation includes questionnaires for the children and their parents on various determinants of dietary behaviour, a 4-day diary to collect information on the child's beverage consumption, and audits at schools. The first evaluation was conducted in Spring 2021 before any intervention, with the two post-intervention evaluations being held in 2022 and 2023. The main quantitative judgement criterion will be the change over time in the mean SB consumption (in ml/day) in the intervention groups compared with the control group. Given the context of the research (school), the safety of the intervention, and the content of data collection, a consent was acknowledged as unnecessary by the Ethical Committee of the Faculty of Psychology (ULB; n°073/2021), but children and parents are explicitly informed of their right to refuse to fill in the questionnaires.

DISCUSSION

Multicomponent interventions based on nutrition and on environmental sustainability, alone or mixed, will provide an original and topical insight into health promotion at school around dietary behaviours. The dissemination plan will enable to widely inform stakeholders, school staff, and families, in addition to the scientific community through the usual medium (articles, conferences), about the research findings in 2024-2025.

TRIAL REGISTRATION

ISRCTN Registry ISRCTN99843102. Retrospectively registered on 25 May 2021.

Best (but oft forgotten) practices: Efficient sample sizes for commonly used trial designs

Designing studies such that they have a high level of power to detect an effect or association of interest is an important tool to improve the quality and reproducibility of findings from such studies. Since resources (research subjects, time, and money) are scarce, it is important to obtain sufficient power with minimum use of such resources. For commonly used randomized trials of the treatment effect on a continuous outcome, designs are presented that minimize the number of subjects or the amount of research budget when aiming for a desired power level. This concerns the optimal allocation of subjects to treatments and, in case of nested designs such as cluster-randomized trials and multicenter trials, also the optimal number of centers versus the number of persons per center. Since such optimal designs require knowledge of parameters of the analysis model that are not known in the design stage, in particular outcome variances, maximin designs are presented. These designs guarantee a prespecified power level for plausible ranges of the unknown parameters and minimize research costs for the worst-case values of these parameters. The focus is on a 2-group parallel design, the AB/BA crossover design, and cluster-randomized and multicenter trials with a continuous outcome. How to calculate sample sizes for maximin designs is illustrated for examples from nutrition. Several computer programs that are helpful in calculating sample sizes for optimal and maximin designs are discussed as well as some results on optimal designs for other types of outcomes.

Cluster randomised trial to evaluate comprehensive approach to hypertension management in Nepal: a study protocol

INTRODUCTION

Despite having effective approaches for hypertension management including use of antihypertensive medication, monitoring of blood pressure and lifestyle modification many people with hypertension in Nepal remain undetected and untreated. A comprehensive intervention which provides personalised counselling on lifestyle modification, medication adherence together with support for regular monitoring of blood pressure is expected to achieve well controlled blood pressure.

METHODS AND ANALYSIS

This is a community-based, non-blinded, parallel group, two-arm cluster randomised controlled trial, with an allocation ratio of 1:1, conducted in Budhanilkantha municipality, Nepal. Ten health facilities and their catchment area are randomly allocated to either of the two arms. 1250 individuals aged 18 years and older with an established diagnosis of hypertension will be recruited. The intervention arm receives a comprehensive hypertension management package that includes blood pressure audit by health workers, home-based patient support by community health workers to engage patient and family members in providing tailored educational counselling on behavioural and lifestyle changes in addition to routine care. The control arm includes routine hypertension care. Trained enumerators will ensure consent and collect data. Outcome data on blood pressure, weight, waist and hip circumference will be measured and self-reported data on diet, lifestyle, medication adherence and hypertension knowledge will be registered at 11 months' follow-up. The change in outcome measures will be compared by intention to treat, using a generalised linear mixed model. A formative assessment will be conducted using semistructured interviews and focus group discussions to explore factors affecting hypertension management. A mix-method approach will be applied for process evaluation to explore acceptability, adoption, fidelity, feasibility and coverage.

ETHICS AND DISSEMINATION

Ethics approval was obtained from Nepal Health Research Council (682/2021) and Regional Committee for Medical and Health Research Ethics, Norway (399479). The findings will be disseminated in peer-reviewed journal articles and with decision makers in Nepal.

Effectiveness and Safety of Inactivated SARS-CoV-2 Vaccine (BBIBP-CorV) among Healthcare Workers: A Seven-Month Follow-Up Study at Fifteen Central Hospitals

BACKGROUND

During a pandemic, healthcare workers are at high risk of contracting COVID-19. To protect these important individuals, it is highly recommended that they receive the COVID-19 vaccine. Our study focused on evaluating the safety and efficacy of Egypt's first approved vaccine, the Sinopharm vaccine (BBIBP-CorV), and comparing these findings with other vaccines.

METHODS

An observational study was conducted in fifteen triage and isolation hospitals, from the 1st of March until the end of September 2021. The study included fully vaccinated and unvaccinated participants, and we measured vaccine effectiveness (using 1-aHR), the incidence rate of severely to critically ill hospitalized cases, COVID-19-related work absenteeism, and the safety of the vaccine as outcomes.

RESULTS

Of the 1364 healthcare workers who were interviewed, 1228 agreed to participate. After taking the hazard ratio into account, the vaccine effectiveness was found to be 67% (95% CI, 80-43%) for symptomatic PCR-confirmed cases. The incidence rate ratio for hospitalization was 0.45 (95% CI, 0.15-1.31) in the vaccinated group compared to the unvaccinated group, and there was a significant reduction in absenteeism among the vaccinated group (p < 0.007). Most adverse events were mild and well tolerated. Vaccinated pregnant and lactating mothers did not experience any sentinel adverse events.

CONCLUSION

Our study found that the BBIBP-CorV vaccine was effective in protecting healthcare workers from COVID-19.

A hybrid approach to comparing parallel-group and stepped-wedge cluster-randomized trials with a continuous primary outcome when there is uncertainty in the intra-cluster correlation

BACKGROUND/AIMS

To evaluate how uncertainty in the intra-cluster correlation impacts whether a parallel-group or stepped-wedge cluster-randomized trial design is more efficient in terms of the required sample size, in the case of cross-sectional stepped-wedge cluster-randomized trials and continuous outcome data.

METHODS

We motivate our work by reviewing how the intra-cluster correlation and standard deviation were justified in 54 health technology assessment reports on cluster-randomized trials. To enable uncertainty at the design stage to be incorporated into the design specification, we then describe how sample size calculation can be performed for cluster- randomized trials in the 'hybrid' framework, which places priors on design parameters and controls the expected power in place of the conventional frequentist power. Comparison of the parallel-group and stepped-wedge cluster-randomized trial designs is conducted by placing Beta and truncated Normal priors on the intra-cluster correlation, and a Gamma prior on the standard deviation.

RESULTS

Many Health Technology Assessment reports did not adhere to the Consolidated Standards of Reporting Trials guideline of indicating the uncertainty around the assumed intra-cluster correlation, while others did not justify the assumed intra-cluster correlation or standard deviation. Even for a prior intra-cluster correlation distribution with a small mode, moderate prior densities on high intra-cluster correlation values can lead to a stepped-wedge cluster-randomized trial being more efficient because of the degree to which a stepped-wedge cluster-randomized trial is more efficient for high intra-cluster correlations. With careful specification of the priors, the designs in the hybrid framework can become more robust to, for example, an unexpectedly large value of the outcome variance.

CONCLUSION

When there is difficulty obtaining a reliable value for the intra-cluster correlation to assume at the design stage, the proposed methodology offers an appealing approach to sample size calculation. Often, uncertainty in the intra-cluster correlation will mean a stepped-wedge cluster-randomized trial is more efficient than a parallel-group cluster-randomized trial design.

Sample size calculations for continuous outcomes in clinical nutrition

In nutrition research, sample size calculations for continuous outcomes are important for the planning phase of many randomized trials and could also be relevant for some observational studies such as cohort and cross-sectional studies. However, only little literature dedicated to this topic exists within nutritional science. This article reviews the most common methods for sample size calculations in nutrition research. Approximate formulas are used for explaining concepts and requirements and for working through examples from the literature. Sample size calculations for the various study designs, which are covered, may all be seen as extensions of the sample size calculation for the basic two-group comparison through the application of suitable scaling factors and, possibly, modification of the significance level. The latter is needed for sample size calculations for multi-group designs and designs involving multiple primary outcomes. Like cluster-randomized designs, these types of study designs may be more challenging than standard sample size calculations. In such non-standard scenarios, there may be a need for consulting a biostatistician. Finally, it should be stressed that there may be many ways to plan a study. The final sample size calculation provided for a grant applicant, study protocol, or publication will often not only depend on considerations and input information as described in this article but will also involve restrictions in terms of logistics and/or resources.

Effect of Face-to-Face and WhatsApp Communication of a Theory-Based Health Education Intervention on Breastfeeding Self-Efficacy (SeBF Intervention): Cluster Randomized Controlled Field Trial

Background

The exclusive breastfeeding rate in Malaysia is still not satisfactory. Previous studies have shown that breastfeeding self-efficacy is one of the determinants of exclusive breastfeeding, and it can be improved using social cognitive theory. WhatsApp, which is widely used among Malaysians, could be leveraged as a platform to deliver health education interventions.

Objective

This study aimed to develop, implement, and evaluate the effect of using a face-to-face and WhatsApp-based health education intervention based on social cognitive theory, namely the Self-Efficacy in Breastfeeding (SeBF) module, on mothers' self-efficacy, knowledge, and attitudes in a district in Selangor state.

Methods

This study was a 2-arm, parallel, single-blind, cluster randomized controlled field trial with an intervention and a control group involving primigravida or multigravida mothers who reside in a district in Selangor state and did not exclusively breastfeed during their previous pregnancy. All 12 maternity and pediatric clinics in this district were randomly divided into 6 intervention and 6 control groups. A total of 172 pregnant mothers were randomly assigned to the intervention group (n=86) or the control group (n=86). The control group received usual routine care. The primary outcome was breastfeeding self-efficacy, while secondary outcomes were knowledge and attitude toward breastfeeding. Each subject was assessed at 4 time points: at baseline, immediately after the intervention, 4 weeks post partum, and 8 weeks post partum. Generalized mixed model analysis was applied to measure the effect of health education on breastfeeding self-efficacy, knowledge, and attitude after the intervention.

Results

The response rate was 81% (139/172), with the dropout rate being 7% (6/86) in the intervention group and 31% (27/86) in the control group. In the intent-to-treat analysis, the intervention group showed a significant increase in the mean total breastfeeding self-efficacy score 8 weeks after delivery compared with the control group (F_21,601=111.73, P<.001). In addition, the mean total score for breastfeeding knowledge increased significantly in the intervention group after the intervention compared to the control group (F_21,601=8.33, P<.001). However, no significant difference was found in the mean total score for breastfeeding attitude after the intervention (F_21,602=5.50, P=.47).

Conclusions

Face-to-face and WhatsApp-based participation in the SeBF program, designed on the basis of social cognitive theory, contributed to improved self-efficacy and knowledge about breastfeeding. Further studies need to be conducted with a longer duration (until 6 months post partum) to evaluate its effectiveness in increasing exclusive breastfeeding. Furthermore, new strategies in health education need to be developed to improve breastfeeding attitudes.

Trial Registration

Thaiclinicaltrials.org TCTR20200213004; https://www.thaiclinicaltrials.org/show/TCTR20200213004

Effect, economic and process-evaluation of a generic function focused care program for long-term care; study protocol of a multicenter cluster-randomized trial

BACKGROUND

Nurses are in a key position to stimulate older people to maximize their functional activity and independence. However, nurses still often work in a task-oriented manner and tend to take over tasks unnecessarily. It is evident to support nurses to focus on the capabilities of older people and provide care assistance only when required. Function-Focused Care (FFC) is a holistic care-philosophy aiming to support nurses to deliver care in which functioning and independence of older people is optimized. Dutch and internationally developed FFC-based interventions often lack effectiveness in changing nurses' and client's behavior. Process-evaluations have yielded lessons and implications resulting in the development of an advanced generic FFC-program: the 'SELF-program'. The SELF-program aims to improve activity stimulation behavior of nurses in long-term care services, and with that optimize levels of self-reliance in activities of daily living (ADL) in geriatric clients. The innovative character of the SELF-program lies for example in the application of extended behavior change theory, its interactive nature, and tailoring its components to setting-specific elements and needs of its participants. This paper describes the outline, content and theoretical background of the SELF-program. Subsequently, this paper describes a protocol for the assessment of the program's effect, economic and process-evaluation in a two-arm (SELF-program vs care as usual) multicenter cluster-randomized trial (CRT).

METHOD

The proposed CRT has three objectives, including getting insight into the program's: (1) effectiveness regarding activity stimulation behavior of nurses and self-reliance in ADL of geriatric clients, and (2) cost-effectiveness from a societal perspective including assessments of quality of life and health-care use. Measurements will take place prior to program implementation (baseline), directly after (T1), and in long-term (T2). Parallel to the CRT, a process evaluation will be conducted to provide insight into the program's: (3) feasibility regarding implementation, mechanisms of impact and contextual factors.

DISCUSSION

The SELF-program was developed following the Medical Research Council framework, which addresses the systematic development, feasibility testing, evaluation and implementation of complex interventions. The program has been subjected to a feasibility study before and results of studies described in this protocol are expected to be available from end 2022 onwards.

TRIAL-REGISTRATION

The study is registered in the Dutch Trial Register ( NL9189 ), as of December 22 2020.

Effectiveness of a tailored communication intervention on colonoscopy uptake for firstdegree relatives of colorectal cancer patients: A randomised controlled trial

Objective

To evaluate the effect of a WeChat tailored communication intervention on colonoscopy uptake and health beliefs in Chinese first-degree relatives (FDRs) of colorectal cancer patients.

Methods

This study employed a single-blinded randomized controlled trial. A total of 188 eligible FDRs were recruited and randomly assigned to the tailored intervention group or control group. Health beliefs were assessed at 1 (T1) and 3 months (T2) postintervention. The colonoscopy uptake was verified by medical records at T2. Data were analyzed using binary logistic regression and generalized estimating equation models.

Results

Compared with the participants in the control group, those in the intervention group had a significant improvement in terms of colonoscopy uptake (OR = 2.752, 95% CI: 1.428–5.303, P ​< ​0.01), perceived susceptibility (T1: β ​= ​0.298, 95% CI: ​0.052–0.402, P ​< ​0.05; T2: β ​= ​0.251, 95% CI: ​0.078–0.424, P ​< ​0.001) and cues to action (T1: β ​= ​0.0.264, 95% CI: ​0.138–0.389, P ​< ​0.001; T2: β ​= ​0.327, 95% CI: ​0.195–0.459, P ​< ​0.001) and a significant reduction in perceived barriers (T1: β ​= ​−0.237, 95% CI: ​−0.360−0.115, P ​< ​0.01; T2: β ​= ​−0.196, 95% CI: ​−0.331−0.062, P ​< ​0.01).

Conclusions

This study broadens the application of tailored communication using novel channels in the context of screening in the at-risk Chinese population. The results provide insights on how to improve the intervention by modifying its components and communication channels.

Practical considerations in utilizing cluster randomized controlled trials conducted in biopharmaceutical industry

Cluster randomized controlled trials (cluster RCTs), also known as parallel-arm group-randomized trials, are trials in which the randomized units are groups of participants, as opposed to individual participants. These trials have largely been implemented to address broad public health issues, but with the growing interest in use of real-world data in the regulatory setting, this design may be increasingly considered for industry trials. The key difference between cluster RCTs and traditional RCTs is the intraclass correlation coefficient (ICC) that needs to be considered in cluster RCTs. In this article, we discuss some key practical considerations that are related to ICC in the design, conduct, analysis, and report stages of a cluster RCT. These key considerations related to ICC can lead to improvement in how we translate research findings from cluster RCTs into practices in the biopharmaceutical industry.

Diabetes Prevention Education Program in a population with pre-diabetes in Nepal: a study protocol of a cluster randomised controlled trial (DiPEP)

INTRODUCTION

Evidence suggests that diabetes burden can be reduced by implementing early lifestyle intervention programmes in population with pre-diabetes in high-income countries. However, little is known in developing nations like Nepal. This study aims to assess effectiveness of community-based Diabetes Prevention Education Program (DiPEP) on haemoglobin A1c (HbA1c) level, proportion of pre-diabetes reverting to normoglycaemia, diet, physical activity, weight reduction, diabetes knowledge and health literacy after 6 months of follow-up. Furthermore, we will also conduct qualitative studies to explore experiences of participants of intervention sessions and perception of healthcare workers/volunteers about DiPEP.

METHODS AND ANALYSES

This is a community-based two-arm, open-label, cluster randomised controlled trial. We will randomise 14 clusters into intervention arm and control arm. Estimated total sample size is 448. We will screen individuals without diabetes, aged 18-64 years, and permanent residents of study sites. HbA1c test will be only performed if both Indian Diabetes Risk Score and random blood sugar value are ≥60 and 140-250 mg/dL, respectively. At baseline, participants in intervention arm will receive DiPEP package (including intensive intervention classes, diabetes prevention brochure, exercise calendar and food record booklet), and participants in control arm will be provided only with diabetes prevention brochure. The change in outcome measures will be compared between intervention to control arm after 6 months of follow-up by linear mixed models. Also, we will conduct individual interviews among participants and healthcare workers as part of a qualitative study. We will use thematic analysis to analyse qualitative data.

ETHICS AND DISSEMINATION

Regional Committee for Medical and Health Research Ethics, Norway; Nepal Health Research Council, Nepal and Institutional Review Committee, Kathmandu University School of Medical Sciences have approved the study. The DiPEP package can be implemented in other communities of Nepal if it is effective in preventing diabetes.

TRIAL REGISTRATION NUMBER

NCT04074148, 2019/783.

Power(ful) myths: misconceptions regarding sample size in quality of life research

PURPOSE

Carefully selecting the sample size for a research study is one of the most fundamental ways to utilize resources in an ethical manner, maximize impact and replicability, and minimize research waste when investigating questions relevant to health-related quality of life (HRQOL). Despite an increased focus on sample size in the methodological literature, the topic has received limited attention in the HRQOL field, and there are still misconceptions that can weaken even well-intentioned sample size planning. This article aims to highlight common misconceptions, provide accessible and non-technical corrections to these misconceptions, and show how HRQOL researchers can benefit from a more nuanced understanding of sample size planning.

METHOD

Misconceptions were identified broadly through examples within the health, psychology, and HRQOL literatures. In examining these misconceptions, study-level (e.g., missing data, multilevel designs, multiple reported outcomes) and field-level (e.g., publication bias, replicability) issues relevant to HRQOL research were considered.

RESULTS

Misconceptions include: (a) researchers should use rules of thumb or the largest sample size possible, (b) sample size planning should always focus on power, (c) planned power = actual power, (d) there is only one level of power per study, and (e) power is only relevant for the individual researcher. Throughout the article, major themes linked to these misconceptions are mapped onto recent HRQOL studies to make the connections more tangible.

CONCLUSION

By clarifying several challenges and misconceptions regarding sample size planning and statistical power, HRQOL researchers will have the tools needed to augment the research literature in effective and meaningful ways.

Employing multiple synchronous outcome samples per subject to improve study efficiency

Background

Accuracy can be improved by taking multiple synchronous samples from each subject in a study to estimate the endpoint of interest if sample values are not highly correlated. If feasible, it is useful to assess the value of this cluster approach when planning studies. Multiple assessments may be the only method to increase power to an acceptable level if the number of subjects is limited.

Methods

The main aim is to estimate the difference in outcome between groups of subjects by taking one or more synchronous primary outcome samples or measurements. A summary statistic from multiple samples per subject will typically have a lower sampling error. The number of subjects can be balanced against the number of synchronous samples to minimize the sampling error, subject to design constraints. This approach can include estimating the optimum number of samples given the cost per subject and the cost per sample.

Results

The accuracy improvement achieved by taking multiple samples depends on the intra-class correlation (ICC). The lower the ICC, the greater the benefit that can accrue. If the ICC is high, then a second sample will provide little additional information about the subject’s true value. If the ICC is very low, adding a sample can be equivalent to adding an extra subject. Benefits of multiple samples include the ability to reduce the number of subjects in a study and increase both the power and the available alpha. If, for example, the ICC is 35%, adding a second measurement can be equivalent to adding 48% more subjects to a single measurement study.

Conclusion

A study’s design can sometimes be improved by taking multiple synchronous samples. It is useful to evaluate this strategy as an extension of a single sample design. An Excel workbook is provided to allow researchers to explore the most appropriate number of samples to take in a given setting.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-021-01414-7.

CRTpowerdist: An R package to calculate attained power and construct the power distribution for cross-sectional stepped-wedge and parallel cluster randomized trials

BACKGROUND

The attained power, calculated conditional on the realized allocation, of a clinical trial may differ from the expected power, obtained pre-randomization through averaging over all potential allocations that could be generated by the randomization algorithm (RA). For example, a two-arm trial using a RA that is expected to allocate 20 participants to each arm will attain less than the expected power if by chance it allocates 25 and 15 participants to the arms. Cluster randomized trials with unequal cluster sizes have elevated risk of realizing an allocation that yields an attained power much lower than the expected power when modest numbers of clusters are randomized.

METHOD

We developed the R package CRTpowerdist, which implements both simulations and approximate analytic formulae to calculate the attained powers associated with different realized allocations and constructs the pre-randomization power distribution associated with the RA to facilitate assessing the risk of obtaining inadequate power. The package covers unequal cluster-size, cross-sectional stepped-wedge and parallel cluster randomized trials, with or without stratification. Allowed outcome types are: continuous (Gaussian), binary (Binomial) and count (Poisson). The analytic formulae-based calculations are also implemented in a Shiny app.

RESULTS

The functionality of the CRTpowerdist is illustrated for each type of trial design. The examples show how to obtain the attained power, the power distribution, and the risk of low attained power, using both simulation and analytic formulae.

CONCLUSION

For cluster randomized trials with unequal cluster sizes, the CRTpowerdist package can assist users in identifying an appropriate randomization algorithm by enabling the user to assess the risk that a randomization algorithm will lead to an allocation with inadequate attained power. The Shiny app makes these assessments accessible to researchers who are unable or do not wish to use the CRTpowerdist package.

Methods for dealing with unequal cluster sizes in cluster randomized trials: A scoping review

In a cluster-randomized trial (CRT), the number of participants enrolled often varies across clusters. This variation should be considered during both trial design and data analysis to ensure statistical performance goals are achieved. Most methodological literature on the CRT design has assumed equal cluster sizes. This scoping review focuses on methodology for unequal cluster size CRTs. EMBASE, Medline, Google Scholar, MathSciNet and Web of Science databases were searched to identify English-language articles reporting on methodology for unequal cluster size CRTs published until March 2021. We extracted data on the focus of the paper (power calculation, Type I error etc.), the type of CRT, the type and the range of parameter values investigated (number of clusters, mean cluster size, cluster size coefficient of variation, intra-cluster correlation coefficient, etc.), and the main conclusions. Seventy-nine of 5032 identified papers met the inclusion criteria. Papers primarily focused on the parallel-arm CRT (p-CRT, n = 60, 76%) and the stepped-wedge CRT (n = 14, 18%). Roughly 75% of the papers addressed trial design issues (sample size/power calculation) while 25% focused on analysis considerations (Type I error, bias, etc.). The ranges of parameter values explored varied substantially across different studies. Methods for accounting for unequal cluster sizes in the p-CRT have been investigated extensively for Gaussian and binary outcomes. Synthesizing the findings of these works is difficult as the magnitude of impact of the unequal cluster sizes varies substantially across the combinations and ranges of input parameters. Limited investigations have been done for other combinations of a CRT design by outcome type, particularly methodology involving binary outcomes-the most commonly used type of primary outcome in trials. The paucity of methodological papers outside of the p-CRT with Gaussian or binary outcomes highlights the need for further methodological development to fill the gaps.

Cluster Randomized Trial: Sun Protection Intervention 'Clever in Sun and Shade for Preschools'-Effectiveness and Dissemination

Skin cancer is one of the most common types of cancer and UV radiation is one of the main risk factors. Therefore, sun protection, especially in childhood, is strongly recommended. We examined the effectiveness of the ‘Clever in Sun and Shade for Preschools’ program (CLEVER) in promoting sun protection behavior among preschool staff (trial registration: DRKS00023468) and describe its dissemination. Within a cluster randomized trial with 24 preschools (n = 273 staff members) stating a high need for sun protection measures, an educational workshop for preschool staff and a project kit with materials applicable in preschool groups was provided. Staff members of preschools taking part in CLEVER report significantly stronger sun protection behavior to avoid the sun (effect size [ES] 0.70, 95% confidence interval [CI] 0.04 0.71, p < 0.05) and less perceived impediments to avoid the sun (ES −0.56, CI −0.82 −0.17, p < 0.01) after 12 months as well as higher self-efficacy to avoid the sun (ES 1.09, CI 0.39 1.07, p < 0.001) and to use sunscreen (ES 0.71, CI 0.03 0.88, p < 0.05) after 1 month. Compared to the control group, there was no significant effect on sunscreen use and further psychosocial outcomes. The effectiveness of CLEVER may be underrated due to a high drop-out rate. Within three years, an enhanced free-of-charge program kit, including a media-based workshop and materials, had reached over 4000 preschools, i.e., 7.1% of all daycare centers in Germany. The results show that CLEVER can strengthen sun protection, offer high-quality information at low cost, and is easily disseminable.

The role and challenges of cluster randomised trials for global health

Evaluating whether an intervention works when trialled in groups of individuals can pose complex challenges for clinical research. Cluster randomised controlled trials involve the random allocation of groups or clusters of individuals to receive an intervention, and they are commonly used in global health research. In this paper, we describe the potential reasons for the increasing popularity of cluster trials in low-income and middle-income countries. We also draw on key areas of global health research for an assessment of common trial planning practices, and we address their methodological shortcomings and pitfalls. Lastly, we discuss alternative approaches for population-level intervention trials that could be useful for research undertaken in low-income and middle-income countries for situations in which the use of cluster randomisation might not be appropriate.

Contributions of treatment centre and patient characteristics to patient-reported experience of haemodialysis: a national cross-sectional study

OBJECTIVES

To examine the relative importance of patient and centre level factors in determining self-reported experience of care in patients with advanced kidney disease treated by maintenance haemodialysis (HD).

DESIGN

Analysis of data from a cross sectional national survey; the UK Renal Registry (UKRR) national Kidney patient-reported experience measure (PREM) survey (2018). Centre-level data were obtained from the UKRR report (2018).

SETTING

National survey of patients with advanced kidney disease receiving treatment with maintenance HD in UK renal centres in 2018.

PARTICIPANTS

The Kidney PREM was distributed to all UK renal centres by the UKRR in May 2018. Each centre invited patients receiving outpatient treatment for kidney disease to complete the PREM. These included patients with chronic kidney disease, those receiving dialysis-both HD and peritoneal dialysis, and those with a functioning kidney transplant. There were no formal inclusion/exclusion criteria.

MAIN OUTCOME MEASURES

The Kidney PREM has 38 questions in 13 subscales. Responses were captured using a 7-point Likert scale (never 1, always 7). The primary outcome of interest was the mean PREM score calculated across all questions. Multilevel modelling was used to determine the proportion of variation of the mean PREM score across centres due to patient-related and centre-related factors.

RESULTS

There were records for 8253 HD patients (61% men, 77% white) from 69 renal centres (9-710 patients per centre). There was significant variation in mean PREM score across centres (5.35-6.53). In the multivariable analysis there was some variation in relation to both patient- and centre-level factors but these contributed little to explaining the overall variation. However, multilevel modelling showed that the overwhelming proportion of the explained variance (45%) was explained by variation between centres (40%), only a small proportion of which is identified by measured factors. Only 5% of the variation was related to patient-level factors.

CONCLUSIONS

Centre rather than patient characteristics determine the experience of care of patients receiving HD. Further work is required to define the characteristics of the treating centre which determine patient experience.

Effectiveness of training in guideline-oriented biopsychosocial management of low-back pain in occupational health services - a cluster randomized controlled trial

Objective:

This study aimed to investigate the effectiveness of brief training in the guideline-oriented biopsychosocial management of low-back pain (LBP) in occupational health services using a cluster-randomized design. A small sample of physiotherapists and physicians from the intervention units (N=12) were given three- to seven-day training focusing on the biopsychosocial management of LBP, while professionals in the control units (N=15) received no such training.

Methods:

Eligible patients with LBP, with or without radicular pain, aged 18–65, were invited to participate. A web-based questionnaire was sent to all recruited patients at baseline, three months and one year. The primary outcome measure was disability (Oswestry Disability Index, ODI) over one year. Between-group differences were analyzed using linear and generalized linear mixed models adjusted for baseline-response delay as well as variables showing between-group imbalance at baseline.

Results:

The final study sample comprised 234 and 81 patients in the intervention and control groups, respectively at baseline, and 137 and 47 patients, respectively, at one year. At baseline, the mean duration of pain was longer in the intervention group (P=0.017), and pain-related fear concerning physical activity was lower (P=0.012). We observed no significant difference between the groups’ primary outcome measure (adjusted one-year mean difference in the ODI: 2.3; 95% confidence interval -1.0–5.7; P=0.175) or most secondary outcomes.

Conclusions:

Brief training in guideline-oriented biopsychosocial management of LBP for occupational health professionals did not appear to be effective in reducing patients’ symptom over one-year follow-up compared to treatment as usual.

Evaluation of training in guideline-oriented biopsychosocial management of low back pain in occupational health services: Protocol of a cluster randomized trial

BACKGROUND

To prevent low back pain (LBP) from developing into a prolonged disabling condition, clinical guidelines advocate early stage assessment, risk-screening, and tailored interventions. Occupational health services recommend guideline-oriented biopsychosocial screening and individualized assessment and management. However, it is not known whether training a limited number of health care professionals improves the management process. The primary objective of this study is to investigate whether training in the biopsychosocial practice model is effective in reducing disability. Furthermore, we aim to evaluate health-economic impacts of the training intervention in comparison to usual medical care.

METHODS

The occupational health service units will be allocated into a training or control arm in a two-arm cluster randomized controlled design. The training of occupational physiotherapists and physicians will include the assessment of pain-related psychosocial factors using the STarT Back Tool and the short version of the Örebro Musculoskeletal Pain Screening Questionnaire, the use of an evidence-based patient education booklet as part of the management of LBP, and tailored individualized management of LBP according to risk stratification. The control units will receive no training. The study population will include patients aged 18-65 with nonspecific LBP. The primary outcome is a patient-reported Oswestry Disability Index from baseline to 12 months. By estimating group differences over time, we aim to evaluate the effectiveness of the training intervention in comparison to usual medical care, and to undertake an economic evaluation using individual patients' health care records (participant-level data) and the participating units' registries (cluster-level data). In addition, through interviews and questionnaires, we will explore the health care professionals' conceptions of the adoption of, the barriers to, and the facilitators of the implementation of the practice model.

DISCUSSION

The evaluation of training in the guideline-oriented biopsychosocial management of LBP in occupational health services is justified because LBP represents an enormous burden in terms of work disability.

Peer-Assisted Lifestyle (PAL) intervention: a protocol of a cluster-randomised controlled trial of a health-coaching intervention delivered by veteran peers to improve obesity treatment in primary care

INTRODUCTION

Among US veterans, more than 78% have a body mass index (BMI) in the overweight (≥25 kg/m²) or obese range (≥30 kg/m²). Clinical guidelines recommend multicomponent lifestyle programmes to promote modest, clinically significant body mass (BM) loss. Primary care providers (PCPs) often lack time to counsel and refer patients to intensive programmes (≥6 sessions over 3 months). Using peer coaches to deliver obesity counselling in primary care may increase patient motivation, promote behavioural change and address the specific needs of veterans. We describe the rationale and design of a cluster-randomised controlled trial to test the efficacy of the Peer-Assisted Lifestyle (PAL) intervention compared with enhanced usual care (EUC) to improve BM loss, clinical and behavioural outcomes (aim 1); identify BM-loss predictors (aim 2); and increase PCP counselling (aim 3).

METHODS AND ANALYSIS

We are recruiting 461 veterans aged 18-69 years with obesity or overweight with an obesity-associated condition under the care of a PCP at the Brooklyn campus of the Veterans Affairs NY Harbor Healthcare System. To deliver counselling, PAL uses in-person and telephone-based peer support, a tablet-delivered goal-setting tool and PCP training. Patients in the EUC arm receive non-tailored healthy living handouts. In-person data collection occurs at baseline, month 6 and month 12 for patients in both arms. Repeated measures modelling based on mixed models will compare mean BM loss (primary outcome) between study arms.

ETHICS AND DISSEMINATION

The protocol has been approved by the Institutional Review Board and the Research and Development Committee at the VA NY Harbor Health Systems (#01607). We will disseminate the results via peer-reviewed publications, conference presentations and meetings with stakeholders.

TRIAL REGISTRATION NUMBER

NCT03163264; Pre-results.

Accelerating the conceptual use of behavioral health research in juvenile court decision-making: study protocol

BACKGROUND

The youth criminal-legal system is under heavy political scrutiny with multiple calls for significant transformation. Leaders within the system are faced with rethinking traditional models and are likely to benefit from behavioral health research evidence as they redesign systems. Little is known about how juvenile court systems access and use behavioral health research evidence; further, the field lacks a validated survey measure of behavioral health research use that can be used to evaluate the effectiveness of evidence dissemination interventions for policy and system leaders. Conceptual research use is a particularly salient construct for system reform as it describes the process of shifting awareness and the consideration of new frameworks for action. A tool designed to measure the conceptual use of behavioral health research would advance the field's ability to develop effective models of research evidence dissemination, including collaborative planning models to support the use of behavioral health research in reforms of the criminal-legal system.

METHODS

The ARC Study is a longitudinal, cohort and measurement validation study. It will proceed in two phases. The first phase will focus on measure development using established methods of construct validity (theoretical review, Delphi methods for expert review, cognitive interviewing). The second phase will involve gathering responses from the developed survey to examine scale psychometrics using Rasch analyses, change sensitivity analyses, and associations between research use exposure and conceptual research use among juvenile court leaders. We will recruit juvenile court leaders (judges, administrators, managers, supervisors) from 80 juvenile court jurisdictions with an anticipated sample size of n = 520 respondents.

DISCUSSION

The study will introduce a new measurement tool for the field that will advance implementation science methods for the study of behavioral health research evidence use in complex policy and decision-making interventions. To date, there are few validated survey measures of conceptual research use and no measures that are validated for measuring change in conceptual frameworks over time among agency leaders. While the study is most directly related to leaders in the youth criminal-legal system, the findings are expected to be informative for research focused on leadership and decision-making in diverse fields.

Sample size requirements for detecting treatment effect heterogeneity in cluster randomized trials

Cluster randomized trials (CRTs) refer to experiments with randomization carried out at the cluster or the group level. While numerous statistical methods have been developed for the design and analysis of CRTs, most of the existing methods focused on testing the overall treatment effect across the population characteristics, with few discussions on the differential treatment effect among subpopulations. In addition, the sample size and power requirements for detecting differential treatment effect in CRTs remain unclear, but are helpful for studies planned with such an objective. In this article, we develop a new sample size formula for detecting treatment effect heterogeneity in two-level CRTs for continuous outcomes, continuous or binary covariates measured at cluster or individual level. We also investigate the roles of two intraclass correlation coefficients (ICCs): the adjusted ICC for the outcome of interest and the marginal ICC for the covariate of interest. We further derive a closed-form design effect formula to facilitate the application of the proposed method, and provide extensions to accommodate multiple covariates. Extensive simulations are carried out to validate the proposed formula in finite samples. We find that the empirical power agrees well with the prediction across a range of parameter constellations, when data are analyzed by a linear mixed effects model with a treatment-by-covariate interaction. Finally, we use data from the HF-ACTION study to illustrate the proposed sample size procedure for detecting heterogeneous treatment effects.

Efficient and flexible simulation-based sample size determination for clinical trials with multiple design parameters

Simulation offers a simple and flexible way to estimate the power of a clinical trial when analytic formulae are not available. The computational burden of using simulation has, however, restricted its application to only the simplest of sample size determination problems, often minimising a single parameter (the overall sample size) subject to power being above a target level. We describe a general framework for solving simulation-based sample size determination problems with several design parameters over which to optimise and several conflicting criteria to be minimised. The method is based on an established global optimisation algorithm widely used in the design and analysis of computer experiments, using a non-parametric regression model as an approximation of the true underlying power function. The method is flexible, can be used for almost any problem for which power can be estimated using simulation, and can be implemented using existing statistical software packages. We illustrate its application to a sample size determination problem involving complex clustering structures, two primary endpoints and small sample considerations.

Relative efficiency of equal versus unequal cluster sizes in cluster randomized trials with a small number of clusters

To calculate sample sizes in cluster randomized trials (CRTs), the cluster sizes are usually assumed to be identical across all clusters for simplicity. However, equal cluster sizes are not guaranteed in practice, especially when the number of clusters is limited. Therefore, it is important to understand the relative efficiency (RE) of equal versus unequal cluster sizes when designing CRTs with a limited number of clusters. In this paper, we are interested in the RE of two bias-corrected sandwich estimators of the treatment effect in the Generalized Estimating Equation (GEE) models for CRTs with a small number of clusters. Specifically, we derive the RE of two bias-corrected sandwich estimators for binary, continuous, or count data in CRTs under the assumption of an exchangeable working correlation structure. We consider different scenarios of cluster size distributions and investigate RE performance through simulation studies. We conclude that the number of clusters could be increased by as much as 42% to compensate for efficiency loss due to unequal cluster sizes. Finally, we propose an algorithm of increasing the number of clusters when the coefficient of variation of cluster sizes is known and unknown.

A cluster randomized controlled trial for the Evaluation of routinely Measured PATient reported outcomes in HemodialYsis care (EMPATHY): a study protocol

Background

Kidney failure requiring dialysis is associated with poor health outcomes and health-related quality of life (HRQL). Patient-reported outcome measures (PROMs) capture symptom burden, level of functioning and other outcomes from a patient perspective, and can support clinicians to monitor disease progression, address symptoms, and facilitate patient-centered care. While evidence suggests the use of PROMs in clinical practice can lead to improved patient experience in some settings, the impact on patients’ health outcomes and experiences is not fully understood, and their cost-effectiveness in clinical settings is unknown. This study aims to fill these gaps by evaluating the effectiveness and cost-effectiveness of routinely measuring PROMs on patient-reported experience, clinical outcomes, HRQL, and healthcare utilization.

Methods

The EMPATHY trial is a pragmatic multi-centre cluster randomized controlled trial that will implement and evaluate the use of disease-specific and generic PROMs in three kidney care programs in Canada. In-centre hemodialysis units will be randomized into four groups, whereby patients: 1) complete a disease-specific PROM; 2) complete a generic PROM; 3) complete both types of PROMs; 4) receive usual care and do not complete any PROMs. While clinical care pathways are available to all hemodialysis units in the study, for the three active intervention groups, the results of the PROMs will be linked to treatment aids for clinicians and patients. The primary outcome of this study is patient-provider communication, assessed by the Communication Assessment Tool (CAT). Secondary outcomes include patient management and symptoms, use of healthcare services, and the costs of implementing this intervention will also be estimated. The present protocol fulfilled the Standard Protocol Items: Recommendations for Intervention Trials (SPIRIT) checklist.

Discussion

While using PROMs in clinical practice is supported by theory and rationale, and may engage patients and enhance their role in decisions regarding their care and outcomes, the best approach of their use is still uncertain. It is important to rigorously evaluate such interventions and investments to ensure they provide value for patients and health systems.

Trial registration

Protocol version (1.0) and trial registration data are available on www.clinicaltrials.gov, identifier: NCT03535922, registered May 24, 2018.

The effects of integrating work-related factors and improving cooperation in musculoskeletal physical therapy practice: protocol for the 'WORK TO BE DONE' cluster randomised controlled trial

BACKGROUND

Musculoskeletal disorders (MSDs) are the primary cause of disability worldwide and a major societal burden. Recent qualitative research found that although a patient's work is considered important, physical therapists take work participation insufficiently into account as a determining factor in the treatment of patients with MSDs. Therefore, the aim of this study is to improve the effectiveness of physical therapy (in primary healthcare) with respect to the work participation of employees with MSDs by increasing the knowledge and skills of generalist physical therapists and by improving the collaboration between generalist physical therapists and physical therapists specialised in occupational health.

METHODS/DESIGN

This trial is a two-arm non-blinded cluster randomised controlled trial. Working patients with MSDs visiting a physical therapy practice are the target group. The control group will receive normal physical therapy treatment. The intervention group will receive treatment from a physical therapist with more knowledge about work-related factors and skills in terms of integrating work participation into the patients' care. Data are gathered at baseline (T0), at four months (T1) and eight months (T2) follow-up. Most outcomes will be assessed with validated patient-reported questionnaires. Primary outcomes are the limitations in specific work-related activities and pain during work. Secondary outcomes include limitations in general work-related activities, general pain, quality of life, presenteeism, sick leave (absenteeism), estimated risk for future work disability, work-related psychosocial risk factors, job performance, and work ability. Based on a sample size calculation we need to include 221 patients in each arm (442 in total). During data analysis, each outcome variable will be analysed independently at T1 and at T2 as a dependent variable using the study group as an independent variable. In addition to the quantitative evaluation, a process evaluation will be performed by interviewing physical therapists as well as patients.

DISCUSSION

The trial is expected to result in a more effective physical therapy process for working patients with MSDs. This will lead to a substantial reduction of costs: lower costs thanks to a more effective physical therapy process and lower costs due to less or shorter sick leave and decreased presenteeism.

TRIAL REGISTRATION

Netherlands Trial Register, registration number: NL8518, date of registration 9 April 2020, URL registration: https://www.trialregister.nl/trial/8518.

A tutorial on sample size calculation for multiple-period cluster randomized parallel, cross-over and stepped-wedge trials using the Shiny CRT Calculator

It has long been recognized that sample size calculations for cluster randomized trials require consideration of the correlation between multiple observations within the same cluster. When measurements are taken at anything other than a single point in time, these correlations depend not only on the cluster but also on the time separation between measurements and additionally, on whether different participants (cross-sectional designs) or the same participants (cohort designs) are repeatedly measured. This is particularly relevant in trials with multiple periods of measurement, such as the cluster cross-over and stepped-wedge designs, but also to some degree in parallel designs. Several papers describing sample size methodology for these designs have been published, but this methodology might not be accessible to all researchers. In this article we provide a tutorial on sample size calculation for cluster randomized designs with particular emphasis on designs with multiple periods of measurement and provide a web-based tool, the Shiny CRT Calculator, to allow researchers to easily conduct these sample size calculations. We consider both cross-sectional and cohort designs and allow for a variety of assumed within-cluster correlation structures. We consider cluster heterogeneity in treatment effects (for designs where treatment is crossed with cluster), as well as individually randomized group-treatment trials with differential clustering between arms, for example designs where clustering arises from interventions being delivered in groups. The calculator will compute power or precision, as a function of cluster size or number of clusters, for a wide variety of designs and correlation structures. We illustrate the methodology and the flexibility of the Shiny CRT Calculator using a range of examples.

The Kids Obesity Prevention Program: Cluster Randomized Controlled Trial to Evaluate a Serious Game for the Prevention and Treatment of Childhood Obesity

Background

Health games provide opportunities for the treatment and prevention of childhood obesity. We developed a motion-controlled serious game for children that addresses 3 core topics of nutrition, physical activity, and stress coping. It is the first serious game that extensively targets the dietary energy density principle (DED-P) in relation to nutrition. The game is intended to provide an additional educational component for the prevention and treatment of obesity in children.

Objective

The Kids Obesity Prevention study aimed to evaluate the newly developed game and to evaluate how well children are able to understand and apply the DED-P.

Methods

This cluster randomized controlled trial collected data from 82 primary school children aged 9 to 12 years and their parents at baseline (T0), at 2 weeks after study commencement (T1), and at the 4-week follow-up (T2). The dropout rate was 3.6%. The intervention group (IG) played the game within 2 weeks (2 sessions with different game modules). One part of the game involves selection of food with the lower energy density when presented with a pair of foods. This allows assessment of whether the children have understood the DED-P and whether they can apply it to unknown foods under time pressure. The control group (CG) received a brochure about the food pyramid concept and physical activity. The primary outcome was the gain in knowledge (nutrition and stress coping) and measured with a pretested questionnaire. The secondary outcomes were the maintenance of knowledge, application of the DED-P, feelings during game play, game acceptance, and behavioral measures (physical activity, media consumption, and dietary intake).

Results

The knowledge score ranging from 0 to 100 increased from T0 (IG: 53 [SD 10], CG: 50 [SD 11]) to T1 (IG: 69 [SD 11], CG: 52 [SD 12]) in IG versus CG (P<.001). At T2, the knowledge score of IG remained at the same level as that of T1. Game data showed that after DED-P education, the classification under time pressure of unknown versus known food pairs according to their DED category was similar (hit rate around 70%). Overall, 95% of the children liked the game very much or much. No group changes were observed at the behavioral level.

Conclusions

The Kids Obesity Prevention program sustainably increased knowledge in the areas of nutrition and stress coping, and children were able to apply the DED-P.

Trial Registration

ClinicalTrials.gov NCT02551978; https://clinicaltrials.gov/ct2/show/NCT02551978

Effectiveness of a lumbopelvic monitor and feedback device to change postural behaviour: the ELF cluster randomised controlled trial

OBJECTIVES

The aim of this clustered, randomised controlled trial was to assess the effectiveness of a lumbopelvic postural feedback device for changing postural behaviour in a group of healthcare workers. We hypothesised that workers exposed to auditory postural feedback would reduce the number of times forward bending posture is adopted at work.

METHODS

This was a participant and assessor blinded, randomised, sham-controlled trial with blocked cluster random allocation. We recruited healthcare workers from aged care institutions. Healthcare sites were randomly allocated to the feedback or sham group (SG). A postural monitoring and feedback device was used to monitor and record lumbopelvic forward bending posture, and provided audio feedback whenever the user sustained lumbopelvic forward bending posture that exceeded predefined thresholds. The primary outcome measure was postural behaviour (exceeding thresholds). We used a robust variant of repeated measures mixed-effect model for assessing within-group and between-group differences in postural behaviour.

RESULTS

We recruited 19 sites, and 130 healthcare workers participated. There were no within-group changes on the number of times postural threshold was exceeded at 1-week follow-up (feedback group: -0.7, 95% CI -2.61 to 0.72; SG -0.3, -1.65 to 0.98), and no differences (0.05, 95% CI -1.83 to 1.94) between SG and feedback group.

CONCLUSIONS

Findings from this trial indicate that audio feedback provided by a postural monitor device did not reduce the number of times healthcare workers exceeded the postural threshold.

TRIAL REGISTRATION NUMBER

ACTRN12616000449437.

Positive deviance for dual-method promotion among women in Uganda: study protocol for a cluster randomized controlled trial

Background

Dual-method use is known as the most reliable protection against unintended pregnancies and sexually transmitted infections, including HIV. However, it is not commonly used in sub-Sharan Africa, especially among women using highly effective contraceptives. This article describes a protocol to evaluate the effect of an intervention formulated under the positive deviance approach for promoting dual-method use in Uganda.

Methods

A total of 150 women will be interviewed using a structured questionnaire to find those practicing dual-method use. In-depth interviews will then be conducted with all women using the dual method and 10 women using only highly effective contraceptives to identify their unique practice. Then, a cluster randomized controlled trial will be conducted to examine the effect of an intervention formulated under the positive deviance approach on dual-method uptake and adherence. Twenty health facilities will be randomized to an intervention or control arm and 480 women will be enrolled in each group. The participants will be followed up for 8 months.

Discussion

This trial focuses on women who already adapted dual-method use and identifies their unique solutions to promote dual-method use. This trial could tackle barriers for dual-method use, which expert outsiders may fail to recognize, by analyzing and promulgating their unique behaviors. This study could provide evidence that the positive deviance approach can address unintended pregnancies and sexually transmitted infections as well as other health problems which usual approaches have failed to address.

Trial registration

UMIN-CTR Clinical Trial, UMIN000037065. Registered on 14 June 2019.

Embedded Motivational Interviewing combined with a smartphone app to increase physical activity in people with sub-acute low back pain: Study protocol of a cluster randomised control trial

BACKGROUND

Motivational Interviewing is an evidence-based, client-centred counselling technique that has been used effectively to increase physical activity, including for people with low back pain. One barrier to implementing Motivational Interviewing in health care settings more broadly is the extra treatment time with therapists. The aim of this paper is to describe the design of a cluster randomised controlled trial evaluating the effect of an intervention that pairs Motivational Interviewing embedded into usual physiotherapy care with a specifically designed app to increase physical activity in people with sub-acute low back pain.

METHODS

The study is a cluster randomised controlled in which patients aged over 18 years who have sub-acute low back pain (3-12 weeks duration) are recruited from four public hospital outpatient clinics. Based on the recruitment site, participants either receive usual physiotherapy care or the Motivational Interviewing intervention over 6 consecutive weekly outpatient sessions with a specifically designed app designed to facilitate participant-led physical activity behaviour change in between sessions. Outcome measures assessed at baseline and 7 weeks are: physical activity as measured by accelerometer (primary outcome), and pain-related activity restriction and pain self-efficacy (secondary outcomes). Postintervention interviews with physiotherapists and participants will be conducted as part of a process evaluation.

DISCUSSION

This intervention, which comprises trained physiotherapists conducting conversations about increasing physical activity with their patients in a manner consistent with Motivational Interviewing as part of usual care combined with a specifically designed app, has potential to facilitate behaviour change with minimal extra therapist time.

Specific components of a complex depression care program can affect staff outcomes differently: post-hoc analyses of a stepped-wedge cluster-randomized trial in nursing homes

OBJECTIVE

The Act in case of Depression program showed effects on the quality of life and depression in nursing home (NH) residents. We aimed to explore the effects of this complex multidisciplinary program on job satisfaction, job demands, and autonomy in nursing home staff.

DESIGN

Four data points from a stepped-wedge cluster-randomized trial on patient outcomes were used for secondary analyses on staff outcomes.

SETTING

Sixteen dementia special care and 17 somatic care units in Dutch NHs.Participants were 717 (90.1%) care staff or trainees, 34 (4.3%) paramedical staff, and 45 (5.7%) other staff members.Intervention describes procedures for nursing staff, activity therapists, psychologists, and physicians. It contains evidence-based pathways for depression assessment, treatment, and monitoring treatment results.

RESULTS

Mixed models for intention-to-treat analyses showed no significant changes in job demands, job satisfaction, or autonomy. Models corrected for the ratio of unit residents who received, when indicated, a specific program component revealed reduced job demands and improved job satisfaction and autonomy when treatment procedures were used. A better use of assessment procedures was associated with increased job demands, while conducting monitoring procedures was associated with increased job demands and decreased autonomy.

CONCLUSIONS

Components of complex care programs may affect the staff outcomes in opposite directions and, taken together, produce a zero-sum or a statistically insignificant effect. While implementing treatment protocols affecting patients directly can also improve job outcomes such as satisfaction and autonomy and decrease job demands, it is possible that other procedures of complex programs may have unfavorable effects on job outcomes. It is important to account for specific components of complex interventions when evaluating intervention effects.