The challenge of recruiting control groups. An experiment of different recruitment models in the control group of a clinical psychological postal survey

Methods to increase response to postal and electronic questionnaires

BACKGROUND

Self-administered questionnaires are widely used to collect data in epidemiological research, but non-response reduces the effective sample size and can introduce bias. Finding ways to increase response to postal and electronic questionnaires would improve the quality of epidemiological research.

OBJECTIVES

To identify effective strategies to increase response to postal and electronic questionnaires.

SEARCH METHODS

We searched 14 electronic databases up to December 2021 and manually searched the reference lists of relevant trials and reviews. We contacted the authors of all trials or reviews to ask about unpublished trials; where necessary, we also contacted authors to confirm the methods of allocation used and to clarify results presented.

SELECTION CRITERIA

Randomised trials of methods to increase response to postal or electronic questionnaires. We assessed the eligibility of each trial using pre-defined criteria.

DATA COLLECTION AND ANALYSIS

We extracted data on the trial participants, the intervention, the number randomised to intervention and comparison groups and allocation concealment. For each strategy, we estimated pooled odds ratios (OR) and 95% confidence intervals (CI) in a random-effects model. We assessed evidence for selection bias using Egger's weighted regression method and Begg's rank correlation test and funnel plot. We assessed heterogeneity amongst trial odds ratios using a Chi2 test and quantified the degree of inconsistency between trial results using the I2 statistic.

MAIN RESULTS

Postal We found 670 eligible trials that evaluated over 100 different strategies of increasing response to postal questionnaires. We found substantial heterogeneity amongst trial results in half of the strategies. The odds of response almost doubled when: using monetary incentives (odds ratio (OR) 1.86; 95% confidence interval (CI) 1.73 to 1.99; heterogeneity I2 = 85%); using a telephone reminder (OR 1.96; 95% CI 1.03 to 3.74); and when clinical outcome questions were placed last (OR 2.05; 95% CI 1.00 to 4.24). The odds of response increased by about half when: using a shorter questionnaire (OR 1.58; 95% CI 1.40 to 1.78); contacting participants before sending questionnaires (OR 1.36; 95% CI 1.23 to 1.51; I2 = 87%); incentives were given with questionnaires (i.e. unconditional) rather than when given only after participants had returned their questionnaire (i.e. conditional on response) (OR 1.53; 95% CI 1.35 to 1.74); using personalised SMS reminders (OR 1.53; 95% CI 0.97 to 2.42); using a special (recorded) delivery service (OR 1.68; 95% CI 1.36 to 2.08; I2 = 87%); using electronic reminders (OR 1.60; 95% CI 1.10 to 2.33); using intensive follow-up (OR 1.69; 95% CI 0.93 to 3.06); using a more interesting/salient questionnaire (OR 1.73; 95% CI 1.12 to 2.66); and when mentioning an obligation to respond (OR 1.61; 95% CI 1.16 to 2.22). The odds of response also increased with: non-monetary incentives (OR 1.16; 95% CI 1.11 to 1.21; I2 = 80%); a larger monetary incentive (OR 1.24; 95% CI 1.15 to 1.33); a larger non-monetary incentive (OR 1.15; 95% CI 1.00 to 1.33); when a pen was included (OR 1.44; 95% CI 1.38 to 1.50); using personalised materials (OR 1.15; 95% CI 1.09 to 1.21; I2 = 57%); using a single-sided rather than a double-sided questionnaire (OR 1.13; 95% CI 1.02 to 1.25); using stamped return envelopes rather than franked return envelopes (OR 1.23; 95% CI 1.13 to 1.33; I2 = 69%), assuring confidentiality (OR 1.33; 95% CI 1.24 to 1.42); using first-class outward mailing (OR 1.11; 95% CI 1.02 to 1.21); and when questionnaires originated from a university (OR 1.32; 95% CI 1.13 to 1.54). The odds of response were reduced when the questionnaire included questions of a sensitive nature (OR 0.94; 95% CI 0.88 to 1.00). Electronic We found 88 eligible trials that evaluated over 30 different ways of increasing response to electronic questionnaires. We found substantial heterogeneity amongst trial results in half of the strategies. The odds of response tripled when: using a brief letter rather than a detailed letter (OR 3.26; 95% CI 1.79 to 5.94); and when a picture was included in an email (OR 3.05; 95% CI 1.84 to 5.06; I2 = 19%). The odds of response almost doubled when: using monetary incentives (OR 1.88; 95% CI 1.31 to 2.71; I2 = 79%); and using a more interesting topic (OR 1.85; 95% CI 1.52 to 2.26). The odds of response increased by half when: using non-monetary incentives (OR 1.60; 95% CI 1.25 to 2.05); using shorter e-questionnaires (OR 1.51; 95% CI 1.06 to 2.16; I2 = 94%); and using a more interesting e-questionnaire (OR 1.85; 95% CI 1.52 to 2.26). The odds of response increased by a third when: offering survey results as an incentive (OR 1.36; 95% CI 1.16 to 1.59); using a white background (OR 1.31; 95% CI 1.10 to 1.56); and when stressing the benefits to society of response (OR 1.38; 95% CI 1.07 to 1.78; I2 = 41%). The odds of response also increased with: personalised e-questionnaires (OR 1.24; 95% CI 1.17 to 1.32; I2 = 41%); using a simple header (OR 1.23; 95% CI 1.03 to 1.48); giving a deadline (OR 1.18; 95% CI 1.03 to 1.34); and by giving a longer time estimate for completion (OR 1.25; 95% CI 0.96 to 1.64). The odds of response were reduced when: "Survey" was mentioned in the e-mail subject (OR 0.81; 95% CI 0.67 to 0.97); when the email or the e-questionnaire was from a male investigator, or it included a male signature (OR 0.55; 95% CI 0.38 to 0.80); and by using university sponsorship (OR 0.84; 95%CI 0.69 to 1.01). The odds of response using a postal questionnaire were over twice those using an e-questionnaire (OR 2.33; 95% CI 2.25 to 2.42; I2 = 98%). Response also increased when: providing a choice of response mode (electronic or postal) rather than electronic only (OR 1.76 95% CI 1.67 to 1.85; I2 = 97%); and when administering the e-questionnaire by computer rather than by smartphone (OR 1.62 95% CI 1.36 to 1.94).

AUTHORS' CONCLUSIONS

Researchers using postal and electronic questionnaires can increase response using the strategies shown to be effective in this Cochrane review.

Does usage of monetary incentive impact the involvement in surveys? A systematic review and meta-analysis of 46 randomized controlled trials

BACKGROUND

Surveys are an effective method for collecting a large quantity of data. However, incomplete responses to these surveys can affect the validity of the studies and introduce bias. Recent studies have suggested that monetary incentives may increase survey response rates. We intended to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of monetary incentives on survey participation.

METHODS

A systematic search of electronic databases was conducted to collect studies assessing the impact of monetary incentives on survey participation. The primary outcome of interest was the response rates to incentives: money, lottery, and voucher. We used the Cochrane Collaboration tool to assess the risk of bias in randomized trials. We calculated the rate ratio (RR) with its 95% confidence interval (95% CI) using Review Manager Software (version 5.3). We used random-effects analysis and considered the data statistically significant with a P-value <0.05.

RESULTS

Forty-six RCTs were included. A total of 109,648 participants from 14 countries were involved. The mean age of participants ranged from 15 to more than 60 years, with 27.5% being males, 16.7% being females, and the other 55.8% not reported. Our analysis showed a significant increase in response rate in the incentive group compared to the control group, irrespective of the incentive methods. Money was the most efficient way to increase the response rate (RR: 1.25; 95% CI: 1.16,1.35; P = < 0.00001) compared to voucher (RR: 1.19; 95% CI: 1.08,1.31; P = < 0.0005) and lottery (RR: 1.12; 95% CI: 1.03,1.22; P = < 0.009).

CONCLUSION

Monetary incentives encourage the response rate in surveys. Money was more effective than vouchers or lotteries. Therefore, researchers may include money as an incentive to improve the response rate while conducting surveys.

Sensory experiences of one's deceased spouse in older adults: An analysis of predisposing factors

Objectives This study focuses on pre-disposing factors associated with sensory experiences of the deceased (SED), also called bereavement hallucinations. Even though SED are common among older widowed adults, our knowledge of these experiences is still limited.Method Survey responses were obtained from 310 older widowed participants (M = 70.05 ± 8.39), complemented with data from Danish national registers.Results Hierarchical logistic regression analysis revealed four significant pre-disposing factors: prior experiences of SED in the context of previous significant bereavements (OR = 4.72), a history of interpersonal trauma (OR = 5.8), high pre-death relationship closeness (OR = 2.76) and stronger religious/spiritual worldview (OR = 1.12). No association to registered mental health diagnosis was identified.Conclusion: SED may be considered an interpersonal experience, which may be more likely to occur if the pre-death relationship is described as very close and if the bereaved has previously experienced interpersonal trauma. We argue that SED should not necessarily be considered an indication of neurodegenerative or psychiatric diseases.

A systematic mapping review of interventions to improve adolescent mental health literacy, attitudes and behaviours

AIM

The onset of mental illness is most common in adolescence, therefore mental health promotion efforts frequently target this age group. Evaluation literature in this area is largely segmented into specific domains in terms of settings, countries, and/or groups of young people, but an overall understanding and comparison across these areas is lacking. The current review aims to provide such an overview of interventions/programs which attempt to improve adolescents' mental health literacy, attitudes/stigma and behaviours.

METHODS

A systematic mapping review synthesized the strengths and weaknesses of published interventions/programs to improve mental health outcomes in youth. Ten databases and grey literature sources were searched, and results were categorized according to sample, location/setting, type of information presented, delivery and testing procedures, mental health outcome/s evaluated, and limitations.

RESULTS

One hundred and forty articles met the inclusion criteria; 126 were original records and 14 were reviews. Mental health literacy and attitudes/stigma were examined most frequently, and studies were predominantly conducted in school-based environments and high income economies. Intervention/program effectiveness varied across outcome/s measured, setting, and control group usage, with mental health literacy exhibiting the most positive changes overall. Common limitations included no long-term follow up or control group inclusion.

CONCLUSIONS

Despite generally positive changes seen throughout studies in this area, effectiveness differed across a range of methodological domains. Most research is conducted in schools and higher income economies, but the lack of investigation in other contexts (i.e., internet or community) or lower income countries suggests our understanding in this area is constrained.

Adolescent abuse victims displayed physical health complaints and trauma symptoms during post disclosure interviews

AIM

We investigated whether adolescents who had recently disclosed sexual abuse or family violence displayed more psychological trauma symptoms and physical health complaints than unaffected controls. We also investigated to what degree physical health complaints were associated with trauma symptoms in these abuse victims.

METHODS

Abuse, trauma symptoms and physical health complaints were assessed during face-to-face interviews with 40 sexual abuse victims and 35 family violence victims aged 10-18 years. They had all attended forensic interviews at the Barnehus in Oslo, a specialised Norwegian police unit where evidence is gathered in adolescent-friendly surroundings, from October 2016 to November 2018. Their symptoms were compared with 41 controls from the general population. Linear regression analyses investigated associations between trauma symptoms and physical health complaints.

RESULTS

Sexually abused adolescents displayed higher levels of post-traumatic stress reactions, depression, dissociation and physical health complaints than unaffected controls. Family violence victims displayed higher levels of post-traumatic stress reactions. Trauma symptoms were associated with physical health complaints, and these were most prominent in the adolescents with the highest burden of symptoms.

CONCLUSION

Based on the high burden of symptoms revealed, clinical examinations of abused adolescents should include a systematic assessment of trauma symptoms and physical health complaints.

[Effects of an integrated neighborhood approach on older people's (health-related) quality of life and well-being]

Integrated neighborhood approaches (INAs) are increasingly advocated to support community-dwelling older people; their effectiveness however remains unknown. We evaluated INA effects on older people's (health-related) quality of life (HRQoL) and well-being in Rotterdam. We used a matched quasi-experimental design comparing INA with "usual" care and support. Community-dwelling people (aged ≥70) and control subjects (n = 186 each) were followed over a one-year period (measurements at baseline, 6 and 12 months). Primary outcomes were HRQoL (EQ-5D-3L, SF-20) and well-being (SPF-IL). The effect of INA was analysed with generalized linear mixed modeling of repeated measurements, using both an "intention to treat" and "as treated" approach. The results indicated that pre-intervention participants were significantly older, more often single, less educated, had lower incomes and more likely to have ≥1 disease than control subjects; they had lower well-being, physical functioning, role functioning, and mental health. No substantial difference in well-being or HRQoL was observed between the intervention and control group after 1 year. The lack of effects of INA highlights the complexity of integrated care and support initiatives.

Most response-inducing strategies do not increase participation in observational studies: a systematic review and meta-analysis

OBJECTIVES

To evaluate response-inducing strategies for observational studies using health-related questionnaires or interviews.

STUDY DESIGN AND SETTING

We searched PubMed, EMBASE, CINAHL, PsycINFO, and Web of Science up to December 28, 2017. Studies evaluating the effect of a response-inducing strategy on participation rates of observational studies were included. For each strategy, we estimated pooled response ratios with 95% confidence intervals (CIs) in a Hartung-Knapp/Sidik-Jonkman random effects model with the final participation rate as outcome, stratified for type of participants and method of data collection.

RESULTS

The search yielded 168 eligible studies involving 367,616 potential participants and 33 strategies. Among patients, response-inducing strategies for paper-based questionnaires included unconditional monetary incentives (response ratio 1.15; 95% CI 1.09-1.21) and shorter questionnaires (1.04; 1.02-1.06). Among nonpatients, a personalized mode of delivery (1.47; 1.24-1.74), more expensive mailing type (1.25; 1.00-1.56), unconditional monetary incentives (1.24; 1.12-1.38), prenotification (1.12; 1.03-1.22), unconditional scratch lottery tickets (1.09; 1.01-1.18), and shorter questionnaires (1.06; 1.02-1.11) increased response rates to paper-based questionnaires. For Web-based questionnaires and interviews among nonpatients, response rates were increased by conditional lottery tickets (1.17; 1.02-1.34) and conditional monetary incentives (1.39; 1.01-1.91), respectively.

CONCLUSION

Although the majority of strategies evaluated were unsuccessful, some may increase response rates to observational studies, particularly among nonpatients.

Effects of an integrated neighborhood approach on older people's (health-related) quality of life and well-being

BACKGROUND

Integrated neighborhood approaches (INAs) are increasingly advocated to reinforce formal and informal community networks and support community-dwelling older people. They aim to augment older people's self-management abilities and engage informal networks before seeking professional support. INAs' effectiveness however remains unknown. We evaluated an INA's effects on older people's (health-related) quality of life (HRQoL) and well-being in Rotterdam.

METHODS

We used a matched quasi-experimental design comparing INA with "usual" care and support. Community-dwelling frail older (70+ years) people and frailty- and gender-matched control subjects (n = 186 each) were followed over a 1-year period (measurements at baseline and 6 and 12 months). Primary outcomes were HRQoL (EQ-5D-3L, SF-20) and well-being [social production function instrument for the level of well-being (SPF-IL)]. The effect of INA was analysed using an "intention to treat" and an "as treated" approach.

RESULTS

The results indicated that pre-intervention participants had lower incomes and were significantly older, more often single, less educated and more likely to have ≥1 disease than control subjects; they had lower well-being, physical functioning, role functioning, and mental health. Generalized linear mixed modelling of repeated measurements revealed no substantial difference in well-being or HRQoL between the intervention and control group after 1 year. The small differences we did find in the intention to treat group though were in favour of the control subjects (SF-20 = 6.98, 95 % confidence interval [CI] = 2.45-11.52; SPF-IL = .09, 95 % CI = .01-.17). However, the difference in well-being (SPF-IL) disappeared in the as treated analysis.

CONCLUSIONS

The lack of effects of INA highlights the complexity of integrated care and support initiatives. Barriers associated with meeting the complex, varied needs of frail older people, and those related to dynamic political and social climates challenge initiative effectiveness. Trial registration The research was supported with a grant provided by the Netherlands Organisation for Health Research and Development (ZonMw, project number 314030201) as part of the National Care for the Elderly Programme.

The temporal relationship between change in symptoms of prolonged grief and posttraumatic stress following old age spousal bereavement

BACKGROUND

High levels of prolonged grief symptoms (PGS) and posttraumatic stress symptoms (PTS) are relatively common following bereavement. The two types of bereavement complications share some but not all of the same features. Little research has studied which of the two precedes the other following the death of a loved one. The purpose of this study was to examine the temporal relationship between change in PGS and PTS during the first 4 years following old age spousal loss.

METHODS

Participants were 237 Danes (40% male; mean age = 73 years, SD = 4.4; range 65-81) who during the year of 2006 lost their spouse. Participants completed self-report questionnaires at 6 months (n = 237), 13 months (n = 198), 18 months (n = 192), and 48 months (n = 213) post loss. Main outcome measures were Inventory of Complicated Grief-Revised and the Harvard Trauma Questionnaire.

RESULTS

Lower level mediation analyses were performed. Results indicated that PGS mediated 83% of the relationship between time and PTS, whereas PTS only mediated 17% of the relationship between time and PGS. These results suggest that changes in PGS mediated changes in PTS following spousal bereavement to a greater extent than vice versa.

CONCLUSIONS

The findings in the present study indicate that changes in PGS may precede and potentially directly impact changes in PTS following bereavement. This tentative conclusion points to the potential value of targeting PGS in psychological interventions at an early point in the long-term perspective following old age spousal bereavement.