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Table 1 Approaches to identify and recruit women for the Calcium And Pre-eclampsia (CAP) trial: advantages, difficulties, and lessons learnt

From: Participant recruitment and retention in longitudinal preconception randomized trials: lessons learnt from the Calcium And Pre-eclampsia (CAP) trial

Recruitment approach (sites) Advantages Difficulties Lessons learnt and recommendations for future action
Retrospective identification and recruitment of women
 Searching laboratory or other computerized hospital records to identify potential participants (based on pre-eclampsia diagnosis) from the previous 5 years, then sourcing their contact details via medical records (all countries) • Identified eligible women
• Eligibility was fairly easy to determine
• Large databases
• Women were more likely to be planning a pregnancy due to the time elapsed since their previous pregnancy
• Access to medical records was often slow and depended on the goodwill and availability of laboratory and records department staff
• Recruiters felt uncomfortable asking staff to assist without financial compensation
• Due to poor codification at some sites, computerized hospital records under-reported pre-eclampsia
• Many eligible women were unreachable due to missing, incomplete or redundant contact details
• Response rates were poor: e.g., “For every 40 calls made, about 2 or 3 women agreed to come in for a screening visit”
• Recruitment rates were poor: “…many women were reluctant to say ‘no’ to a request to participate, so they said ‘yes’ but 1 out of every 2 or 3 women did not attend their screening appointments”
• Searching and pre-screening was a laborious process
• Telephone screening was time-consuming and expensive
• Recruiters often made evening telephone calls in efforts to make contact
• Some women were identified more than once and received duplicate calls
• Cold-calling caused alarm (many women thought the recruiters were debt collectors) and women were uncomfortable answering personal questions, such as family planning intentions, over the telephone with a stranger
• Potential participants were finite
• A good source of participants but very laborious and time-consuming
• Meet with the medical records/archives department early on and establish the terms of the access, the work involved, and compensation for additional work if appropriate, e.g., agree a day or days on which trial-related work can be performed
• Include a hospital staff member in the research team to reduce bureaucratic/logistical difficulties in accessing records and registers
• Before starting recruitment, dedicate a recruiter or recruiters to compile a complete list of all potentially eligible and contactable women and schedule all telephonic contacts in an e-calendar
• Have a recruiter dedicated to retrospective pre-screening of these women
• Have a computer dedicated to identification/recruitment activities
• Consider ways of sorting telephonic recruitment, e.g., according to pregnancy outcome, (low) parity, to prioritize women most likely to desire another pregnancy
• Check that newly identified women are not already listed, and have a system in place to prevent duplicating telephone calls
• Establish a threshold number of calls (e.g., 3 or 4) that, if not answered over a period of trying (e.g., 1 month), further calls are stopped, so as not to harass potentially eligible women who do not wish to participate
• Provide recruiters with plenty of mobile phone airtime and ensure at least 1 phone per research staff member
 Searching maternity “high-care” ward registers from the previous 5 years, then sourcing medical records and telephone numbers • Identified eligible women, often with severe PE/E
• Eligibility was fairly easy to determine
• Registers were often missing crucial information, e.g., diagnosis, contact details
• Recruiters often required assistance from busy ward staff to clarify queries, locate registers, etc., and sometimes felt uncomfortable disturbing them
• Searching paper records was a laborious process
• Telephone screening was time-consuming and expensive
• Sometimes involved recruiters making evening telephone calls in efforts to make contact
• As above, women were often alarmed by this cold-calling method
• Potential participants were finite
• Establish a good relationship with the “high-care” staff to facilitate access to ward registers
• Identify a research “champion” among the ward staff and consider ways to incentivize and keep staff informed of trial progress
• Give feedback to departments and encourage in-house training on record keeping
 Searching other records and registers, e.g., previous pre-eclampsia study databases, pediatric records • Identified eligible women
• Eligibility was fairly easy to determine
• Many of the same difficulties as above, such as redundant contact details and time-consuming work
• Response and recruitment rates were poor
• Probably not a good use of trial resources
 Advertising with posters • Identified eligible women
• Respondents were usually interested in participating
• Easy to implement
• Posters also served to remind clinical staff of the trial
• Women exposed to poster advertising in clinics were usually unwell, pregnant, or requiring contraception, so eligible participants were limited
• Hospital records were often not available for women referred from community clinics, which made screening and baseline data collection challenging
• Clinic staff had limited availability and recruiters found it challenging to inform them about the trial or interest them in promoting the trial
• Posters were removed or damaged in some clinics and needed replacing
• Respondents had to bear the initial cost of a telephone call, which may have put some women off responding
• A good supplementary activity but yields may not be high
• Budget for design and printing of promotional posters (or advertisements)
• Consider ways of incentivizing clinic staff to identify and encourage potentially eligible respondents
• Visits clinics at regular intervals to update staff and replace posters if necessary
• Give a free-call option or make it clear on the poster that recruiters will call respondents back if they reply by text
 Advertising in newspapers • Respondents were usually interested in participating • Newspaper advertising was expensive (both to design and print) and response rates were low, possibly because many women do not spend money on newspapers
• Pregnant women and other ineligible women often responded
• Hospital records were often not available, which made screening and baseline data collection challenging
• Avoid advertising in the general press
• Identify and consider other appropriate site-specific media, e.g., “free” local newspapers/magazines that appeal to women
• Use of flyers may be more efficient and less expensive as it reaches larger numbers of community women, gives more information
• Budget for design and printing of advertisements
 Presenting on radio talk-shows • Identified potentially eligible women in the community
• Respondents were usually interested in participating
• Wide exposure
• Radio stations were busy and it was difficult to get slots on talk-shows, therefore, this promotional activity was only done once • Radio advertising, as well as talk-shows, may be a good supplementary strategy if resources allow (ads are repeated, unlike talk-shows, which are usually one-off)
• Above the cost of the advert, investigators would need to budget for airtime costs, which vary according to the station, time of day, and length. Alternatively, some radio stations offer “live-reads” by the presenter, which might be more cost-effective
 Using LHWs to promote participation through community outreach (door-to-door visits, community clinics) • Identified potentially eligible women in the community
• Fair number of referrals initially
• Easy to trace participants recruited this way when they missed appointments because of the LHW contact
• Many ineligible women were referred by LHWs
• Transport money and incentives, such as promotional T-shirts and mugs, were provided to LHWs employed by city council clinics; however, it was difficult to keep LHWs incentivized and referrals declined over time
• The area covered by each LHW was finite
• Train LHWs and provide checklists for them on which to base referrals
• Provide supervision for LHW with regular feedback
• Improve incentives for LHWs
• Use LHWs to distribute flyers in their communities to increase exposure
• Budget for LHW training day, supervision, transport money, and incentives
Prospective identification and recruitment of women
 Maternity “high-care” ward, postnatal ward and gynecology ward visits • Identified eligible women
• Allowed a personal face-to-face approach
• Good for identification of potential future participants but not good for (immediate) recruitment as most postnatal women were already using long-acting contraception and were, therefore, temporarily ineligible
• Potential participants were often unwell or traumatized, therefore, were not ready to be engaged with information on future research and pregnancy
• There were also ethical considerations, as women were vulnerable, some after having had a near-death experience or having lost their baby
• Recruiters needed permission to enter wards and sometimes felt like they were being a nuisance
• The process was time-consuming: ward registers were often incomplete so it was necessary to “trawl through the entire ward looking at each bed-letter”
• Eligible women delivering during the weekend could be missed
• Recruiters found it difficult to interest ward staff, including doctors, in identifying potential participants (few women were recruited by such referrals)
• Establish a good relationship with ward staff to facilitate access to current ward registers and bed-letters and keep staff updated on the trial progress, e.g., by arranging meetings with them
• Identify key staff members who will notify recruiters about potential participants, ideally on a daily basis, and especially about those women who deliver and are discharged during the weekend. Shared online spreadsheets can be useful for this purpose
• Subsequent recruitment is most likely to be successful if the potential participant has met the recruiter previously face-to-face
• Establish a support network for women with newborn loss to help maintain contact with potentially eligible postnatal women, and to facilitate discussion about the trial at a later date
• Have a system in place to sort temporarily ineligible women according to methods of contraception (with date of next injection, if applicable) so that the timing of subsequent attempt/s to recruit are appropriate
• During subsequent calls to elicit participants, recruiters should be aware of the outcome of the recent pregnancy, particularly in the event of stillbirth, and should be mindful of the woman’s emotional needs
 Antenatal ward visits • Identified future eligible women
• Allowed a personal face-to-face approach
• Women in the antenatal wards were temporarily ineligible for a potentially long period before being eligible
• It was easy to duplicate entries of potential participants
• Have a system in place to sort temporarily ineligible women according to gestational age at initial contact so that the timing of subsequent attempt/s to recruit are appropriate (e.g., 3-monthly intervals)
• Marking patient folders (e.g., with a highlighter or sticker) once they have been identified reduces recruiter effort and the risk of duplicate entries
 Postnatal clinic and gynecology outpatient clinic visits • Identified women keen to engage with the health system regarding future pregnancy and usually willing to participate
• Allowed a personal face-to-face approach
• Good recruitment source
• Minimal difficulties were noted with this approach, which facilitates immediate recruitment • Establish a good relationship with clinic staff to facilitate notification about potentially eligible women, ideally on a daily basis
• Recruiter “business” cards and flyers for women to take home were useful with this approach
• Consider ways to incentivize clinic staff and keep them updated about trial progress
 Baby clinic visits • Identified eligible women
• Personal face-to-face approach
• Poor response/recruitment
• Many women attending “high-care” baby clinics said they did not want another baby
• Probably not a good use of resources
 Other outpatient departments and pharmacy waiting-rooms • Identified some eligible women
• Waiting-rooms have a “captive audience”
• People in these settings (particularly where there were long queues) often appeared anxious and impatient to have their needs attended to, so “were not interested in listening” to research staff. One recruiter stated that “they were very bored and noisy”
• Yields with this method were low
• This approach might work best in settings with a dedicated pharmacy waiting-room or queue for women
  1. Abbreviations: LHW lay health worker, LMICs low- and middle-income countries, PE/E pre-eclampsia/eclampsia