Randomized trial within a trial of yellow 'post-it notes' did not improve questionnaire response rates among participants in a trial of treatments for neck pain.

Rationale: Attrition is a threat to the validity of randomized trials. Few randomized studies have been conducted within randomized trials to test methods of reducing attrition.

Aim: To test whether using yellow post-it notes on follow-up questionnaires in the ATLAS treatment trial for neck pain reduces attrition.

Alexander Technique Lessons, Acupuncture Sessions or usual care for patients with chronic neck pain (ATLAS): study protocol for a randomised controlled trial.

Background: Chronic neck pain is a common condition in the adult population. More research is needed to evaluate interventions aiming to facilitate beneficial long-term change. We propose to evaluate the effect of Alexander Technique lessons and acupuncture in a rigorously conducted pragmatic trial with an embedded qualitative study.

Yoga for chronic low back pain: a randomized trial.

Background: Previous studies indicate that yoga may be an effective treatment for chronic or recurrent low back pain.

Objective: To compare the effectiveness of yoga and usual care for chronic or recurrent low back pain.

Design: Parallel-group, randomized, controlled trial using computer-generated randomization conducted from April 2007 to March 2010.

Electronic reminders did not improve postal questionnaire response rates or response times: a randomized controlled trial.

Objective: We aim to evaluate the effectiveness of electronic reminders (ERs) to improve the response rates and time to response of postal questionnaires in a health research setting.

Study Design And Setting: This pragmatic randomized controlled trial (RCT) was nested within a multicenter RCT of yoga for lower back pain. Participants who provided an electronic mail address and/or mobile phone number were randomized to receive an ER or no reminder (controls) on the day they were due to receive a follow-up questionnaire.