Poster advertisements in practice waiting rooms to recruit patients to the Treatment In Morning vs. Evening (TIME) online study.

Patient recruitment continues to be the most important, most difficult and least predictable aspect of clinical trials 1. Prolonged or insufficient recruitment has adverse scientific, as well as economic and ethical consequences. It increases cost and time taken, can result in trial termination, and failure to recruit the required numbers can reduce the statistical power of the study 2. Although the effects of poster advertising have previously had mixed results 3-5, we sought to determine if a poster campaign in primary care waiting rooms for an online study could be successful in bringing the Treatment In Morning vs. Evening (TIME) study to the attention of patients. The TIME study is an online only study where participants self-enrol and are randomized to take their hypertensive medication in the morning or the evening. In 2012 the addresses for every general practice in the UK (n = 10 418) and all prescribing cost centres in England and Wales (n = 4740), which include other prescribing units such as walk-in clinics and prisons etc., were obtained. Each address was sent a TIME study poster (Figure 1) along with a letter explaining the research project, a reply slip and pre-paid return envelope. Letters asked for the A3 poster to be displayed in an area visible to the general public in the hope patients would see the poster and register with the website (www.timestudy.co.uk) if eligible. Out of 15 158 letters sent to practices and prescribing centres, 1 155 responses were received (7.6%). 753 agreed to display the TIME poster, 376 refused and there were 26 incomplete reply forms. The cost for the mailing was £10 975, £5065 for printing and £5910 for postage. After 2 months a second round of posters was sent to a random 15% of addresses which did not respond to the first mailing. On this occasion the letter was addressed randomly to a general practitioner (GP) or the practice nurse to see if this had an impact on the response rate. We selected 2330 addresses at random from non-responders of the first mailing. 1220 letters were addressed to the practice nurse and 1110 to a practice GP. 193 responses were received (8.3%). 106 replies came from practice nurses and 87 from GPs. 122 replies agreed to display the study poster. The cost of the second mailing was £1607.70. We tracked recruitment, during study enrolment, and asked participants to tell us how they had learned about the study. The pilot phase of the TIME study randomized 548 participants by all methods including poster advertising but only 52 individuals indicated they enrolled after seeing the study poster and only 40 of those went on to be randomized into the study. Online studies have the advantage of being less expensive to run. Patients recruited by advertisements to a single centre study do not require individual regional NHS Research & Development approvals, so bureaucracy, costs and delays of doing research studies are mitigated. Unfortunately we were unable to achieve suitable recruitment by poster advertising. TIME found about 1 in 30 participants written to by their GP will enrol and be randomized. In order to recruit the 10 000 participants needed to power the study the British Heart Foundation has funded the study to write to 300 000 hypertensive subjects. Had all general practices and prescribing cost centres displayed the poster, the cost per randomized participant (£18) would not have differed greatly from the cost of GPs writing to patients with hypertension in their practice. Poster advertising alone would not have succeeded, regardless of poster uptake. The poster campaign for TIME was unsuccessful, both in engaging general practices and recruiting patients. General practices lack sufficient resources, or time to engage adequately with poster advertisements. Unless this changes, trial resources would be better spent on other forms of recruitment. All authors have completed the Unified Competing Interest form at http://www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare no support from any organization for the submitted work, no financial relationships with any organizations that might have an interest in the submitted work in the previous 3 years and no other relationships or activities that could appear to have influenced the submitted work.