Using modified intention-to-treat as a principal stratum estimator for failure to initiate treatment

User engagement in clinical trials of digital mental health interventions: a systematic review

INTRODUCTION

Digital mental health interventions (DMHIs) overcome traditional barriers enabling wider access to mental health support and allowing individuals to manage their treatment. How individuals engage with DMHIs impacts the intervention effect. This review determined whether the impact of user engagement was assessed in the intervention effect in Randomised Controlled Trials (RCTs) evaluating DMHIs targeting common mental disorders (CMDs).

METHODS

This systematic review was registered on Prospero (CRD42021249503). RCTs published between 01/01/2016 and 17/09/2021 were included if evaluated DMHIs were delivered by app or website; targeted patients with a CMD without non-CMD comorbidities (e.g., diabetes); and were self-guided. Databases searched: Medline; PsycInfo; Embase; and CENTRAL. All data was double extracted. A meta-analysis compared intervention effect estimates when accounting for engagement and when engagement was ignored.

RESULTS

We identified 184 articles randomising 43,529 participants. Interventions were delivered predominantly via websites (145, 78.8%) and 140 (76.1%) articles reported engagement data. All primary analyses adopted treatment policy strategies, ignoring engagement levels. Only 19 (10.3%) articles provided additional intervention effect estimates accounting for user engagement: 2 (10.5%) conducted a complier-average-causal effect (CACE) analysis (principal stratum strategy) and 17 (89.5%) used a less-preferred per-protocol (PP) population excluding individuals failing to meet engagement criteria (estimand strategies unclear). Meta-analysis for PP estimates, when accounting for user engagement, changed the standardised effect to -0.18 95% CI (-0.32, -0.04) from - 0.14 95% CI (-0.24, -0.03) and sample sizes reduced by 33% decreasing precision, whereas meta-analysis for CACE estimates were - 0.19 95% CI (-0.42, 0.03) from - 0.16 95% CI (-0.38, 0.06) with no sample size decrease and less impact on precision. DISCUSSION: Many articles report user engagement metrics but few assessed the impact on the intervention effect missing opportunities to answer important patient centred questions for how well DMHIs work for engaged users. Defining engagement in this area is complex, more research is needed to obtain ways to categorise this into groups. However, the majority that considered engagement in analysis used approaches most likely to induce bias.

Prospective Randomized Phase 2 Trial of Hypofractionated Stereotactic Radiation Therapy of 25 Gy in 5 Fractions Compared With 35 Gy in 5 Fractions in the Reirradiation of Recurrent Glioblastoma

PURPOSE

The aim of this work was to investigate whether reirradiation of recurrent glioblastoma with hypofractionated stereotactic radiation therapy (HSRT) consisting of 35 Gy in 5 fractions (35 Gy/5 fx) compared with 25 Gy in 5 fractions (25 Gy/5 fx) improves outcomes while maintaining acceptable toxicity.

METHODS AND MATERIALS

We conducted a prospective randomized phase 2 trial involving patients with recurrent glioblastoma (per the 2007 and 2016 World Health Organization classification). A minimum interval from first radiation therapy of 5 months and gross tumor volume of 150 cc were required. Patients were randomized 1:1 to receive HSRT alone in 25 Gy/5 fx or 35 Gy/5 fx. The primary endpoint was progression-free survival (PFS). We used a randomized phase 2 screening design with a 2-sided α of 0.15 for the primary endpoint.

RESULTS

From 2011 to 2019, 40 patients were randomized and received HSRT, with 20 patients in each group. The median age was 50 years (range, 27-71); a new resection before HSRT was performed in 75% of patients. The median PFS was 4.9 months in the 25 Gy/5 fx group and 5.2 months in the 35 Gy/5 fx group (P = .23). Six-month PFS was similar at 40% (85% CI, 24%-55%) for both groups. The median overall survival (OS) was 9.2 months in the 25 Gy/5 fx group and 10 months in the 35 Gy/5 fx group (P = .201). Grade ≥3 necrosis was numerically higher in the 35 Gy/5 fx group (3 [16%] vs 1 [5%]), but the difference was not statistically significant (P = .267). In an exploratory analysis, median OS of patients who developed treatment-related necrosis was 14.1 months, and that of patients who did not was 8.7 months (P = .003).

CONCLUSIONS

HSRT alone with 35 Gy/5 fx was not superior to 25 Gy/5 fx in terms of PFS or OS. Due to a potential increase in the rate of clinically meaningful treatment-related necrosis, we suggest 25 Gy/5 fx as the standard dose in HSRT alone. During follow-up, attention should be given to differentiating tumor progression from potentially manageable complications.

Changing diagnostic criteria for gestational diabetes (CDC4G) in Sweden: A stepped wedge cluster randomised trial

BACKGROUND

The World Health Organisation (WHO) 2013 diagnostic criteria for gestational diabetes mellitus (GDM) has been criticised due to the limited evidence of benefits on pregnancy outcomes in different populations when switching from previously higher glycemic thresholds to the lower WHO-2013 diagnostic criteria. The aim of this study was to determine whether the switch from previous Swedish (SWE-GDM) to the WHO-2013 GDM criteria in Sweden following risk factor-based screening improves pregnancy outcomes.

METHODS AND FINDINGS

A stepped wedge cluster randomised trial was performed between January 1 and December 31, 2018 in 11 clusters (17 delivery units) across Sweden, including all pregnancies under care and excluding preexisting diabetes, gastric bypass surgery, or multifetal pregnancies from the analysis. After implementation of uniform clinical and laboratory guidelines, a number of clusters were randomised to intervention (switch to WHO-2013 GDM criteria) each month from February to November 2018. The primary outcome was large for gestational age (LGA, defined as birth weight >90th percentile). Other secondary and prespecified outcomes included maternal and neonatal birth complications. Primary analysis was by modified intention to treat (mITT), excluding 3 clusters that were randomised before study start but were unable to implement the intervention. Prespecified subgroup analysis was undertaken among those discordant for the definition of GDM. Multilevel mixed regression models were used to compare outcome LGA between WHO-2013 and SWE-GDM groups adjusted for clusters, time periods, and potential confounders. Multiple imputation was used for missing potential confounding variables. In the mITT analysis, 47 080 pregnancies were included with 6 882 (14.6%) oral glucose tolerance tests (OGTTs) performed. The GDM prevalence increased from 595/22 797 (2.6%) to 1 591/24 283 (6.6%) after the intervention. In the mITT population, the switch was associated with no change in primary outcome LGA (2 790/24 209 (11.5%) versus 2 584/22 707 (11.4%)) producing an adjusted risk ratio (aRR) of 0.97 (95% confidence interval 0.91 to 1.02, p = 0.26). In the subgroup, the prevalence of LGA was 273/956 (28.8%) before and 278/1 239 (22.5%) after the switch, aRR 0.87 (95% CI 0.75 to 1.01, p = 0.076). No serious events were reported. Potential limitations of this trial are mainly due to the trial design, including failure to adhere to guidelines within and between the clusters and influences of unidentified temporal variations.

CONCLUSIONS

In this study, implementing the WHO-2013 criteria in Sweden with risk factor-based screening did not significantly reduce LGA prevalence defined as birth weight >90th percentile, in the total population, or in the subgroup discordant for the definition of GDM. Future studies are needed to evaluate the effects of treating different glucose thresholds during pregnancy in different populations, with different screening strategies and clinical management guidelines, to optimise women's and children's health in the short and long term.

TRIAL REGISTRATION

The trial is registered with ISRCTN (41918550).

In-classroom physical activity breaks program among school children in Sri Lanka: study protocol for a randomized controlled trial

Background

The problem of sedentary behavior among primary school children is alarming, with numbers gradually increasing worldwide, including Sri Lanka. Physical activity interventions within classroom settings have been acknowledged as a critical strategy to increase students' movement behaviors while enhancing their academic achievement and health. Yet, the busy curriculum and challenging educational demands encourage more sedentary classroom behavior. Hence, this study aims to develop and evaluate an in-classroom physical activity breaks (IcPAB) intervention among fifth graders in Sri Lanka.

Methods

The study will adopt a randomized controlled trial (RCT), comprising an in-classroom physical activity breaks program group and a control group to evaluate the effects of IcPAB on academic achievement, movement behaviors and health outcomes. The intervention design is based on the capability (C), opportunity (O) and motivation (M) behavior (B) (COM-B) model. A least 198 fifth graders will be recruited from two schools in Uva province, Sri Lanka. The recruitment process will start in late 2022. Class teachers of the intervention group will implement 5-min activity breaks at least three times a day after completing a training session. The primary variables include mathematics and reading achievement. The secondary variables include physical activity levels, steps count, sedentary behavior, body mass index, aerobic fitness, and perceived stress. Data collection will be implemented at pre-test and post-test, respectively. Intervention fidelity and the process will also be evaluated.

Discussion

The IcPAB is designed to prevent pure educational time loss by introducing curriculum-integrated short bouts of physical active breaks into the classroom routine. If the IcPAB is effective, it can (1) improve the mathematics and reading achievement of fifth-grade girls and boys, which is a significant factor determining the performance at the Grade Five National Scholarship Examination in Sri Lanka; (2) improve movement behaviors as well as physical and mental health outcomes among primary school students. Sequentially, the IcPAB will enrich school-based physical activity intervention approaches which can in turn bring academic and health benefits to primary school children in Sri Lanka.

Trial registration

The first version of the trial was registered with the ISRCTN registry (Ref: ISRCTN52180050) on 20/07/2022.

Estimands in CNS trials - A review of strategies for addressing intercurrent events

Background

The estimands framework represents a significant innovation for the design, conduct, analysis, and interpretation of clinical trials. An aim of the framework is to increase precision and transparency on the handling of intercurrent events (IEs), defined as events occurring after treatment initiation and affecting the endpoint. While the experience in constructing and reporting estimands in the published literature is limited, developers performing confirmatory studies are already making use of the new paradigm, allowing to survey the strategies proposed by applicants and endorsed by regulators.

Methods

To identify strategies for handling IEs in confirmatory central nervous system (CNS) trials, we searched scientific advice letters issued by the European Medicines Agency (EMA) between 2017 and 2022. We developed a categorisation of the IEs and classified, according to the strategies defined in the framework, the strategies proposed by the Applicants and recommended by the agency. Strategies proposed and recommended were summarised by category of IEs, and the rationale for the choices was analysed qualitatively.

Results

In total, 170 IEs were identified in 52 confirmatory trials. A clear preference for the treatment policy strategy for treatment discontinuation and for the hypothetical strategy for pandemic-related disruptions was identified. For other categories of IEs, there are more mixed patterns.

Discussion

This study highlights the multidimensional nature of choosing a strategy for an IE. For different occurring IEs in confirmatory CNS trials different strategies are of regulatory interest, depending on the trial objective, underlying disease properties, rarity of disease, as well as frequency and timing of IEs and their relatedness to the disease.

Short-term effects and safety of a natural oral supplement containing glucosinolates, phytosterols, and citrus flavonoids compared with hormone treatment for the management of postmenopausal symptomatic women: a pilot single-center randomized phase 2 clinical trial

OBJECTIVE

This study aimed to evaluate the short-term efficacy and safety of an oral herbal supplement containing glucosinolates, phytosterols, and citrus flavonoids for menopausal symptoms in comparison with estrogen plus progestogen therapy (EPT) among postmenopausal women.

METHODS

This was a pilot single-blinded, three-armed phase II randomized clinical trial, controlled with EPT. Sixty participants were randomly assigned to receive treatment for 3 months: (1) an oral herbal supplement of 1,500 mg/d (G1, n = 20), (2) an oral herbal supplement of 3,000 mg/d (G2, n = 20), or (3) conjugated equine estrogens 0.625 mg/d plus medroxyprogesterone acetate of 5 mg/d (EPT group, n = 20). The primary endpoint was the intensity of menopausal symptoms as measured using the Menopause-Specific Quality of Life Questionnaire (global and domain scores). The Menopause-Specific Quality of Life Questionnaire uses a 7-point scale to rate the symptom intensity, with higher scores indicating severity. The secondary endpoints were hormonal, lipid, and safety profiles.

RESULTS

Fifty-four participants (n = 54) completed the study. The mean, model-estimated, and global menopausal symptom scores at 3 months were 85.8 in the EPT group, 61.3 in G1, and 62.5 in G2. Participants treated with the herbal compound had lower global (13.7 [6.9-20.4], P < 0.001) and physical symptom scores (6.6 [1.6-11.5], P = 0.002) on the second month and lower psychosocial symptom scores (3.8 [1.3 to 6.3], P < 0.001) on the third month of follow-up, compared with EPT. Conversely, participants receiving EPT showed better outcomes on vasomotor symptoms since the first month of treatment (-6.1 [-8.3 to -4.0], P < 0.001). The EPT group exhibited higher values of estradiol and lower follicle-stimulating hormone and luteinizing hormone since the first month of follow-up. Also, total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol were significantly higher in this group than in G2.

CONCLUSIONS

In this small single-blind exploratory trial, the oral herbal supplement was more efficacious in reducing global, physical, and psychosocial menopausal symptoms in the short term than EPT. However, further studies are needed to adequately assess the efficacy and safety of this herbal supplement in the treatment of menopausal symptoms.

Pulmonary Lobectomy for Early-Stage Lung Cancer with Uniportal versus Three-Portal Video-Assisted Thoracic Surgery: Results from a Single-Centre Randomized Clinical Trial

Video-assisted thoracic surgery (VATS) is a consolidated approach; however, there is no consensus on the number of ports leading to less postoperative pain. We compared early postoperative pain after uniportal and three-portal VATS lobectomy for early-stage NSCLC. In this randomized clinical trial, patients undergoing VATS lobectomy were randomly assigned to receive uniportal (U-VATS Group) or three-portal (T-VATS Group) VATS. The inclusion criteria were age ≤ 80 years and ASA < 4. The exclusion criteria were clinical T3, previous thoracic surgery, induction therapy, chest radiotherapy, connective tissue or vascular diseases, major organ failure, and analgesics or corticosteroids use. The postoperative analgesia protocol was based on NRS. Pain was measured as analgesic consumption; the secondary endpoints were intra- and postoperative complications, conversion rate, surgical time, dissected lymph nodes, hospital stay, and respiratory function. Out of 302 eligible patients, 120 were included; demographics were distributed homogeneously. The mean cumulative morphine consumption (CMC) in the U-VATS Group after 7 days was lower than in the T-VATS Group (77.4 mg vs. 90.1 mg, p = 0.003). Intraoperative variables and postoperative complications were comparable. The 30-day intercostal neuralgia rate was lower in the U-VATS Group, without reaching statistical significance. Patients undergoing U-VATS showed a lower analgesic consumption compared with the T-VATS Group; analgesic consumption was moderate in both groups.

Eliminating Ambiguous Treatment Effects Using Estimands

Most reported treatment effects in medical research studies are ambiguously defined, which can lead to misinterpretation of study results. This is because most authors do not attempt to describe what the treatment effect represents, and instead require readers to deduce this based on the reported statistical methods. However, this approach is challenging, because many methods provide counterintuitive results. For example, some methods include data from all patients, yet the resulting treatment effect applies only to a subset of patients, whereas other methods will exclude certain patients while results will apply to everyone. Additionally, some analyses provide estimates pertaining to hypothetical settings in which patients never die or discontinue treatment. Herein we introduce estimands as a solution to the aforementioned problem. An estimand is a clear description of what the treatment effect represents, thus saving readers the necessity of trying to infer this from study methods and potentially getting it wrong. We provide examples of how estimands can remove ambiguity from reported treatment effects and describe their current use in practice. The crux of our argument is that readers should not have to infer what investigators are estimating; they should be told explicitly.

Fluid Optimisation in Emergency Laparotomy (FLO-ELA) Trial: study protocol for a multi-centre randomised trial of cardiac output-guided fluid therapy compared to usual care in patients undergoing major emergency gastrointestinal surgery

INTRODUCTION

Postoperative morbidity and mortality in patients undergoing major emergency gastrointestinal surgery are a major burden on healthcare systems. Optimal management of perioperative intravenous fluids may reduce mortality rates and improve outcomes from surgery. Previous small trials of cardiac-output guided haemodynamic therapy algorithms in patients undergoing gastrointestinal surgery have suggested this intervention results in reduced complications and a modest reduction in mortality. However, this existing evidence is based mainly on elective (planned) surgery, with little evaluation in the emergency setting. There are fundamental clinical and pathophysiological differences between the planned and emergency surgical setting which may influence the effects of this intervention. A large definitive trial in emergency surgery is needed to confirm or refute the potential benefits observed in elective surgery and to inform widespread clinical practice.

METHODS

The FLO-ELA trial is a multi-centre, parallel-group, open, randomised controlled trial. 3138 patients aged 50 and over undergoing major emergency gastrointestinal surgery will be randomly allocated in a 1:1 ratio using minimisation to minimally invasive cardiac output monitoring to guide protocolised administration of intra-venous fluid, or usual care without cardiac output monitoring. The trial intervention will be carried out during surgery and for up to 6 h postoperatively. The trial is funded through an efficient design call by the National Institute for Health and Care Research Health Technology Assessment (NIHR HTA) programme and uses existing routinely collected datasets for the majority of data collection. The primary outcome is the number of days alive and out of hospital within 90 days of randomisation. Participants and those delivering the intervention will not be blinded to treatment allocation. Participant recruitment started in September 2017 with a 1-year internal pilot phase and is ongoing at the time of publication.

DISCUSSION

This will be the largest contemporary randomised trial examining the effectiveness of perioperative cardiac output-guided haemodynamic therapy in patients undergoing major emergency gastrointestinal surgery. The multi-centre design and broad inclusion criteria support the external validity of the trial. Although the clinical teams delivering the trial interventions will not be blinded, significant trial outcome measures are objective and not subject to detection bias.

TRIAL REGISTRATION

ISRCTN 14729158. Registered on 02 May 2017.