Longitudinal Clinical Trial Recruitment and Retention Challenges in the Burn Population: Lessons Learned From a Trial Examining a Novel Intervention for Chronic Neuropathic Symptoms

Abstract

Long-term trials are key to understanding chronic symptoms such as pain and itch. However, challenges such as high attrition rates and poor recruitment are common when conducting research. The aim of this work was to explore these issues within a long-term randomized control trial using transcranial direct current stimulation to treat pain and itch. This parallel double blinded, placebo-controlled randomized trial was comprised of 15 transcranial direct current stimulation visits and 7 follow-up visits. Participants were over the age of 18, had a burn injury that occurred at least 3 weeks before enrollment, and reported having pain and/or itch that was moderate to severe in intensity. A total of 31 subjects were randomized into either an active or sham transcranial direct current stimulation groups. There were no significant differences between the groups in terms of age, race, education, baseline depression, or anxiety. The median dropout time was at visit 19 (visit 16 [SE = 1.98] for the sham group and visit 19 [SE = 1.98] for the active group). Analysis showed no differences in the dropout rate between groups [χ2(1) = 0.003, P = .954]. The dropout rate was 46.7% for the sham group and 43.8% for the active group. Overall, 45.2% of the subjects dropped out of the trial. Long-term clinical trials are an essential part of evaluating interventions for symptoms such as chronic pain and itch. However, as seen in this trial, long-term studies in the burn population often face recruitment and adherence challenges.

Methods and strategies of tDCS for the treatment of pain: current status and future directions

“…Recently, thanks to the development of computer FEM models and more complex tDCS devices allowing up to 32 stimulating electrodes, high-density tDCS [32] and network-based tDCS [33] protocols have been tested with promising results compared to conventional montages. The development of home-based devices is assumed to be determinant for the clinical translation of tDCS as it overcomes the issue of patients' travel to a research institution or hospital and therefore, high rate of drop-outs [34,35]. Increase in current intensity thought to induce strong neuroplastic effects has also been tested without causing any significant side effects [36].…”

A review of burn symptoms and potential novel neural targets for non-invasive brain stimulation for treatment of burn sequelae

“…However, current literature on NIBS in burn for treating these and other associated symptoms remains limited and future trials are merited to investigate the efficacy of this approach. Specifically, home-based supervised devices may be utilized in order to limit attrition rates as observed in previous trials [127]. Our review of the neural circuitry involved in post burn symptoms and suggested targeted areas for stimulation provides a spring board for future study initiatives.…”

“…Recently, some studies have utilized home-based tDCS devices with promising results and, most importantly, with no side-effects [123À125]. Thus, home-based supervised sessions, as recommended by Charvet and colleagues [126], could be an alternative to facilitate tDCS and tACS implementation and reduce attrition rates as often observed in clinical trials of long duration [127], as well as to promote long-lasting tES-related effects. Besides the number of sessions, the intensity of stimulation is another parameter to take into account.…”

Recruitment characteristics and non-adherence associated factors of fibromyalgia patients in a randomized clinical trial: A retrospective survival analysis

“…Supporting this finding, another study found that around 36% of withdraws were related to protocol issues as the duration of the study, length of procedures, and other 33% were related to inconvenience as taking time out of work and distance [ 52 ]. In fact, as shown in other stimulation sessions, the number of sessions seems to be related to the dropout rate [ 53 ]. However, the use of online visits might improve this recruitment and the adherence rate [ 54 ].…”