How evidence based are recruitment strategies to randomized controlled trials in primary care? Experience from seven studies

Repeat emergency medical services use by older adults in a rural community: impact on research methods and study length

OBJECTIVES

To evaluate the proportion of emergency medical services (EMS) requests in a rural community made by unique, noninstitutionalized older adults, or individuals making their first request for EMS assistance during the study period, and the impact on research parameters.

METHODS

This study was a retrospective chart review of patients aged 65 years and older cared for by the Geneseo Fire Department Ambulance between February 2004 and May 2005 (period 1) and between July 2006 and October 2007 (period 2). The Geneseo Fire Department Ambulance response territory is a rural community in Upstate New York. We obtained demographic information including age, race, gender, call location, and the frequency of EMS use from the medical record, as well as clinical information including level of prehospital care, chief complaint, and disposition. Descriptive statistics were used for the analysis, along with 95% confidence intervals.

RESULTS

Over two 16-month periods, approximately 70% of the EMS calls by community-dwelling (noninstitutionalized) older adults were from unique individuals. The monthly proportion ranged from 75-100% during the first four months to 43-80% for the remaining 12 months for both groups.

CONCLUSION

In rural, prehospital studies that enroll older adults and last more than four months, approximately 70% of EMS requests are made by unique older adults, or individuals making their first request for EMS assistance. Investigators must consider these results when estimating the enrollment period for prehospital studies.

Maximising recruitment and retention of general practices in clinical trials: a case study

BACKGROUND

There is limited evidence regarding the factors that facilitate recruitment and retention of general practices in clinical trials. It is therefore pertinent to consider the factors that facilitate research in primary care.

AIM

To formulate hypotheses about effective ways of recruiting and retaining practices to clinical trials, based on a case study.

DESIGN OF STUDY

Case study of practice recruitment and retention to a trial of delivering antenatal sickle cell and thalassaemia screening.

SETTING

Two UK primary care trusts with 123 practices, with a high incidence of sickle cell and thalassaemia, and high levels of social deprivation.

METHOD

Practices were invited to take part in the trial using a research information sheet for practices. Invitations were sent to all practice managers, GPs, practice nurses, and nurse practitioners. Expenses of approximately pound 3000 per practice were available. Practices and the research team signed research activity agreements, detailing a payment schedule based on deliverables. Semi-structured interviews were completed with 20 GPs who participated in the trial. Outcome measures were the number of practices recruited to, and completing, the trial.

RESULTS

Four practices did not agree to randomisation and were excluded. Of 119 eligible practices, 29 expressed an interest in participation. Two practices withdrew from the trial and 27 participated (two hosted pilot studies and 25 completed the trial), giving a retention rate of 93% (27/29). The 27 participating practices did not differ from non-participating practices in list size, number of GPs, social deprivation, or minority ethnic group composition of the practice population.

CONCLUSION

Three factors appeared important in recruiting practices: research topic, invitation method, and interest in research. Three factors appeared important in retaining practices: good communication, easy data-collection methods, and payment upon meeting pre-agreed targets. The effectiveness of these factors at facilitating recruitment and retention requires assessment in experimental studies.

Changing clinicians' behavior: a randomized controlled trial of fees and education

The fissure-sealing of newly erupted molars is an effective caries prevention treatment, but remains underutilized. Two plausible reasons are the financial disincentive produced by the dental remuneration system, and dentists' lack of awareness of evidence-based practice. The primary hypothesis was that implementation strategies based on remuneration or training in evidence-based healthcare would produce a higher proportion of children receiving sealed second permanent molars than standard care. The four study arms were: fee per sealant treatment, education in evidence-based practice, fee plus education, and control. A cost-effectiveness analysis was conducted. Analysis was based on 133 dentists and 2833 children. After adjustment for baseline differences, the primary outcome was 9.8% higher when a fee was offered. The education intervention had no statistically significant effect. 'Fee only' was the most cost-effective intervention. The study contributes to the incentives in health care provision debate, and led to the introduction of a direct fee for this treatment.

Effect of incentives and mailing features on online health program enrollment

BACKGROUND

With the growing use of Internet-based interventions, strategies are needed to encourage broader participation. This study examined the effects of combinations of monetary incentives and mailing characteristics on enrollment, retention, and cost effectiveness for an online health program.

METHODS

In 2004, a recruitment letter was mailed to randomly selected Midwestern integrated health system members aged 21-65 and stratified by gender and race/ethnicity; recipients were randomly pre-assigned to one of 24 combinations of incentives and various mailing characteristics. Enrollment and 3-month retention rates were measured by completion of online surveys. Analysis, completed in 2005, compared enrollment and retention factors using t tests and chi-square tests. Multivariate logistic regression modeling assessed the probability of enrollment and retention.

RESULTS

Of 12,289 subjects, 531 (4.3%) enrolled online, ranging from 1% to 11% by incentive combination. Highest enrollment occurred with unconditional incentives, and responses varied by gender. Retention rates ranged from 0% to 100%, with highest retention linked to higher-value incentives. The combination of a $2 bill prepaid incentive and the promise of $20 for retention (10% enrollment and 71% retention) was optimal, considering per-subject recruitment costs ($32 enrollment, $70 retention) and equivalent enrollment by gender and race/ethnicity.

CONCLUSIONS

Cash incentives improved enrollment in an online health program. Men and women responded differently to mailing characteristics and incentives. Including a small prepaid monetary incentive ($2 or $5) and revealing the higher promised-retention incentive was cost effective and boosted enrollment.

Pragmatic trials in primary care. Methodological challenges and solutions demonstrated by the DIAMOND-study

Background

Pragmatic randomised controlled trials are often used in primary care to evaluate the effect of a treatment strategy. In these trials it is difficult to achieve both high internal validity and high generalisability. This article will discuss several methodological challenges in designing and conducting a pragmatic primary care based randomised controlled trial, based on our experiences in the DIAMOND-study and will discuss the rationale behind the choices we made. From the successes as well as the problems we experienced the quality of future pragmatic trials may benefit.

Discussion

The first challenge concerned choosing the clinically most relevant interventions to compare and enable blinded comparison, since two interventions had very different appearances. By adding treatment steps to one treatment arm and adding placebo to both treatment arms both internal and external validity were optimized. Nevertheless, although blinding is essential for a high internal validity, it should be warily considered in a pragmatic trial because it decreases external validity. Choosing and recruiting a representative selection of participants was the second challenge. We succeeded in retrieving a representative relatively large patient sample by carefully choosing (few) inclusion and exclusion criteria, by random selection, by paying much attention to participant recruitment and taking the participant's reasons to participate into account. Good and regular contact with the GPs and patients was to our opinion essential. The third challenge was to choose the primary outcome, which needed to reflect effectiveness of the treatment in every day practice. We also designed our protocol to follow every day practice as much as possible, although standardized treatment is usually preferred in trials. The aim of this was our fourth challenge: to limit the number of protocol deviations and increase external validity.

Summary

It is challenging to design and conduct a pragmatic trial. Thanks to thorough preparation, we were able to collect highly valid data. To our opinion, a critical deliberation of where on the pragmatic – explanatory spectrum you want your trial to be on forehand, in combination with consulting publications especially on patient recruitment procedures, has been helpful in conducting a successful trial.

Recruitment and retention in a multicentre randomised controlled trial in Bell's palsy: a case study

BACKGROUND

It is notoriously difficult to recruit patients to randomised controlled trials in primary care. This is particularly true when the disease process under investigation occurs relatively infrequently and must be investigated during a brief time window. Bell's palsy, an acute unilateral paralysis of the facial nerve is just such a relatively rare condition. In this case study we describe the organisational issues presented in setting up a large randomised controlled trial of the management of Bell's palsy across primary and secondary care in Scotland and how we managed to successfully recruit and retain patients presenting in the community.

METHODS

Where possible we used existing evidence on recruitment strategies to maximise recruitment and retention. We consider that the key issues in the success of this study were; the fact that the research was seen as clinically important by the clinicians who had initial responsibility for recruitment; employing an experienced trial co-ordinator and dedicated researchers willing to recruit participants seven days per week and to visit them at home at a time convenient to them, hence reducing missed patients and ensuring they were retained in the study; national visibility and repeated publicity at a local level delivered by locally based principal investigators well known to their primary care community; encouraging recruitment by payment to practices and reducing the workload of the referring doctors by providing immediate access to specialist care; good collaboration between primary and secondary care and basing local investigators in the otolarnygology trial centres

RESULTS

Although the recruitment rate did not meet our initial expectations, enhanced retention meant that we exceeded our planned target of recruiting 550 patients within the planned time-scale.

CONCLUSION

While difficult, recruitment to and retention within multi-centre trials from primary care can be successfully achieved through the application of the best available evidence, establishing good relationships with practices, minimising the workload of those involved in recruitment and offering enhanced care to all participants. Primary care trialists should describe their experiences of the methods used to persuade patients to participate in their trials when publishing their results.

Survey among 78 studies showed that Lasagna's law holds in Dutch primary care research

OBJECTIVE

Research in general practice has grown considerably over the past decades, but many projects face problems when recruiting patients. Lasagna's Law states that medical investigators overestimate the number of patients available for a research study. We aimed to assess factors related to success or failure of recruitment in general practice research.

STUDY DESIGN AND SETTING

Survey among investigators involved in primary care research in The Netherlands. Face-to-face interviews were held with investigators of 78 projects, assessing study design and fieldwork characteristics as well as success of patient recruitment.

RESULTS

Studies that focused on prevalent cases were more successful than studies that required incident cases. Studies in which the general practitioner (GP) had to be alert during consultations were less successful. When the GP or practice assistant was the first to inform the patient about the study, patient recruitment was less successful than when the patient received a letter by mail. There was a strong association among these three factors.

CONCLUSION

Lasagna's Law also holds in Dutch primary care research: many studies face recruitment problems. Awareness of study characteristics affecting participation of GPs and patients may help investigators to improve their study design.

Inhaled corticosteroids for recurrent respiratory symptoms in preschool children in general practice: randomized controlled trial

BACKGROUND

Therapy with inhaled corticosteroids (ICS) is beneficial in patients with asthma. However, in preschool children with symptoms like cough, wheeze, or shortness of breath diagnosing asthma is difficult. Therefore, the role of ICS in the management of preschool children with recurrent respiratory symptoms is unclear. We assessed the effectiveness of ICS in preschool children with recurrent respiratory symptoms in general practice.

METHODS

In this multicenter, randomized, double blind, placebo controlled trial, 96 children aged 1-5 years consulting their general practitioners for recurrent respiratory symptoms and in whom treatment with ICS was considered by the general practitioner were randomly allocated to receive ICS (fluticasone propionate 200 mcg/day by metered dose inhaler/spacer combination) or placebo for 6 months. Outcome assessments were carried out 1, 3, and 6 months after randomization. The primary outcome measure was the symptom score (cough, shortness of breath and wheeze during day and night) as measured by a symptom diary card. Secondary endpoints were symptom-free days, use of rescue medication, adverse events, and lung function variables as measured by the interrupter technique and forced oscillation technique.

RESULTS

During the 6 months treatment period, symptoms improved in both groups, with no differences between ICS and placebo. In addition, none of the secondary outcome parameters showed differences between both treatment groups.

CONCLUSION

ICS treatment has no beneficial effect in preschool children with recurrent respiratory symptoms in general practice. We therefore recommend a watchful waiting policy with only symptomatic treatment in these children. General practitioners and pediatricians should be aware of the high probability of overtreatment when prescribing ICS in these children.

Lessons learned in participant recruitment and retention: the EXCITE trial

Participant recruitment is considered the most difficult aspect of the research process. Despite the integral role of recruitment in randomized clinical trials, publication of data defining the recruitment effort is not routine in rehabilitation initiatives. The recruitment process for the Extremity Constraint-Induced Therapy Evaluation (EXCITE) trial illustrates obstacles to and strategies for participant accrual and retention that are inherent in rehabilitation clinical trials. The purpose of this article is to increase awareness of the multiple facets of recruitment necessary for successful clinical trials, thus supporting the continued development of evidence-based practice in physical therapy. The Recruitment Index is presented as a variable to measure recruitment efficacy. In addition, ethical aspects of recruitment are explored, including informed consent and the concept of therapeutic misconception.

[Organisational issues in implementing clinical trials in primary care]

OBJECTIVE

To identify health professionals concerns on the organisational issues of a randomised clinical trial.

DESIGN

A qualitative cross-sectional, descriptive study.

SETTING

Primary Care Area 11, Madrid, Spain.

PARTICIPANTS

Twenty-four doctors and nurses from 4 primary care teams.

METHOD

Three planning meetings with researchers. Design of an anonymous self-administered questionnaire to collect researchers' perceptions on design, method, and organisation during the implementation of a clinical trial.

RESULTS

The prestige of being involved in a multi-centre nationwide project, the training sessions offered, a primary care research topic, a working team model of doctor and nurse, and the support provided by team from the 11th Area, were the main organisational incentives. Lack of time, increased clinic workload, and methodological difficulties are discouraging issues. 79.2% (19/24) of the researchers returned the questionnaire. 94.7% (18/19) considered themselves highly motivated. 84.2% (16/19) of researchers, the time required to complete recruitment was reasonable. The 57.9% (13/19) spent 20-25 minutes collecting data at the interview. Cooperation between doctors and nurses had been effective for 68.4% (13/19) of researchers. 89.4% (17/18) considered that support from the Area 11 organisers was useful.

CONCLUSIONS

Organisational barriers for implementation are: complexity of data collection at the recruitment interview, design and methodological issues too unrealistic for a primary care setting, and lack of time and extra workload at consultations. The factors that make organisation easier are: having a high level of motivation, sharing workload with other professionals, and support provided by organisers of the trial.

A systematic review of reasons for nonentry of eligible patients into surgical randomized controlled trials

BACKGROUND

The low recruitment rates into surgical randomized controlled trials (RCTs) threaten the validity of their findings. We reviewed the reasons for nonentry of eligible patients into surgical RCTs that would form the basis for future prospective research.

METHODS

A systematic review of the English language literature for studies reporting reasons for nonentry of eligible patients into surgical RCTs and of recommendations made to improve the low recruitment rates.

RESULTS

We reviewed 401 articles, including 94 articles presenting the results of 62 studies: 23 reports of recruitment into real surgical RCTs, 11 surveys of patients regarding hypothetical surgical RCTs, 10 surveys of clinicians and 18 literature reviews. The most frequently reported patient-related reasons for nonentry into surgical RCTs were preference for one form of treatment, dislike of the idea of randomization, and the potential for increased demands. Distrust of clinicians caused by a struggle to understand, explicit refusal of a no-treatment (placebo) arm, and the mere inability to make a decision were frequently reported in studies of real RCTs and patient surveys, but were not emphasized in surveys of clinicians and review articles. Difficulties with informed consent, the complexity of study protocols, and the clinicians' loss of motivation attributable to lack of recognition were the most commonly reported clinician-related reasons.

CONCLUSIONS

There seems to be a discrepancy between real reasons for nonentry of eligible patients into surgical RCTS and those perceived by the clinicians, which require further prospective research. A summary and discussion of main recommendations sighted in the literature is presented.

Recruiting subjects for acute stroke trials: a meta-analysis

BACKGROUND AND PURPOSE

Recruitment rate is a major determinant of the duration, cost, and feasibility of acute stroke trials.

METHODS

We performed a meta-analysis of all randomized, controlled trials of > or =300 subjects that were designed to evaluate the efficacy of a medical intervention for the treatment of acute ischemic stroke. Data about trial recruitment, organization, and inclusion/exclusion criteria were abstracted independently by 2 reviewers who applied predefined criteria. Recruitment efficiency was defined as the number of subjects enrolled per study center per month of recruitment.

RESULTS

Of 32 trials meeting inclusion criteria, the average recruitment efficiency was 0.79 subjects per center per month (range 0.08 to 3.7). Recruitment efficiency did not vary by geographic region (P=0.36), but trials conducted in 1 country had more efficient recruitment than international studies (P=0.03), and recruitment efficiency declined with each percentage increase in the total number of study centers (P=0.002). The primary study entry criteria that predicted reduced recruitment efficiency were the maximum allowable time from stroke to study enrollment (P=0.002) and the exclusion of mild strokes (P=0.009). Trials with a treatment window >6 hours had approximately double the recruitment rates of trials that used treatment windows < or =6 hours (1.03 versus 0.52 patients per center per month).

CONCLUSIONS

Recruitment rates for acute stroke trials are influenced by organizational structure and study entry criteria. Characterizing predictors of recruitment may help optimize future trial design.

Recruitment to a trial of self-care skills training in long-term health conditions: analysis of the impact of patient attitudes and preferences

The rise of evidence-based practice has highlighted the importance of effective recruitment to randomised controlled trials if studies are to be adequately powered and valid. However, there are also increasing concerns about patient preferences and choice within trials. The current authors are involved in a trial of a programme to provide self-care skills training for people with long-term health conditions (the 'Expert Patients Programme'), and during the design stage there were significant concerns about the impact of patient preferences on the feasibility and validity of the study, because recruitment required that patients risk randomisation to a waiting list control group. This paper first details the issues raised in this trial, and the methods used to attempt to overcome them. Data on recruitment rates, loss to follow up and patient decision making about participation are presented, which suggested that initial assumptions about the impact of patient preferences were incorrect. Key lessons concerning preferences in this patient population and related issues in trial administration are then discussed.

Clinical trials in dental primary care: what research methods have been used to produce reliable evidence?

OBJECTIVE

To identify controlled clinical trials done exclusively in dental primary care and to classify the research according to design. Details of any procedures used to recruit general dental practitioners and any special organisational arrangements were also collected.

DESIGN

A scoping literature review.

SETTING

Dental primary care defined as general dental practice, community and school dental settings.

PARTICIPANTS

Published randomised controlled trials using randomised or quasi randomised approaches and controlled clinical trials were considered for inclusion in the review. Reports were excluded if they did not describe either a randomised controlled trial or a controlled trial. Studies were excluded if the setting was not primary dental care or the intervention was for non-dental conditions. Conference abstracts without a full report and trials published in a language other than English were also excluded.

MAIN OUTCOMES

Experimental and quasi-experimental designs, clinical areas and different kinds of strategies used to recruit dentists, any organisational arrangements made to support research in dental primary care.

RESULTS

The search of the Cochrane Oral Health Group Controlled Trials Register found 174 articles. Forty-three randomised controlled trials met the inclusion criteria. Trials to evaluate the effects of interventions for types of anaesthesia, periodontal diseases, smoking cessation techniques, dental materials, organisational aspects of dental care, patient anxiety, post extraction healing rates, antibiotics were identified. All were done in general dental practice. Trials in school and community settings were also included.

CONCLUSIONS

Practice-based research needs to be encouraged to provide dental primary care with relevant evidence upon which effective treatment can be based. This review shows there are few trials done in dental primary care to inform clinical practice, most of which have been reported since 1997. The range of trial designs shows that this method of evaluation can be used to evaluate dental primary care interventions and this is promising for those with an interest in improving dental patient outcomes. More research on how to recruit dentists into clinical trial research must be done.

When free condoms and spermicide are not enough: barriers and solutions to participant recruitment to community-based trials

While randomised controlled trials remain the accepted 'gold standard' in medical research, participant recruitment is often problematic, particularly with primary care trials or those requiring healthy volunteers. Such difficulties can jeopardise the trial, leading to early abandonment, reduced statistical power or timetable and budget overruns. Substantial changes in recruitment plans may reduce the generalisability of the research. In order to overcome some of the more common recruitment difficulties, it is important that researchers share their recruitment strategy successes and failures. We report our experience of recruiting healthy volunteers to a condom trial, based within primary care and community populations. This was an RCT of the effect that using an additional spermicidal lubricant has on condom failure. We originally aimed to recruit entirely from Family Planning Clinics, but eventually required a wide variety of strategies. Targeted mailings, newspaper coverage and electronic 'posters' were among the most successful we used to bolster clinic recruitment. Concerned at our slow recruitment rates, we conducted a questionnaire survey investigating the reasons for participation and non-participation in the research completed by 101 trial participants, 112 decliners and 90 controls (total 303). The most important reasons given for taking part included 'considering the research to be important' (85%), 'wanting to help the researchers' (70%), 'having time to help' (62%) and 'getting free condoms and lubricant' (56%). The most popular reasons for declining were 'not wanting to use condoms' (38%), 'partner's unwillingness to take part' (29%), 'not wanting to alter usual contraceptive practice' (27%), 'not having time' (21%). Contrary to expectations, embarrassment and fears about confidentiality were relatively unimportant factors in this decision. In conclusion, the key to attaining recruitment targets was the core research team taking an active part, working closely with clinic staff and maintaining tight control of the process. Altruism remains a powerful motivation for participants, supported by incentives and procedural details to minimise personal inconvenience. Even for intimate research topics, these general factors outweigh specific issues.