Kravitz RL, et al. - This randomized clinical trial determined whether patients with chronic musculoskeletal pain (CMSP) randomized to participate in an n-of-1 trial supported by a mobile health (mHealth) app would experience less pain and improved global health, adherence, satisfaction, and shared decision-making vs patients assigned to usual care. Results showed that mHealth-supported n-of-1 trials were feasible and related to a satisfactory user experience; however, n-of-1 trial participation did not significantly improve pain interference at 6 months vs usual care.

Methods

• This trial compared participation in an individualized, mHealth-supported n-of-1 trial to usual care.
• Eligible participants (n=215) had CMSP for ≥ 6 weeks, had a smartphone or tablet with a data plan, were enrolled in northern California from July 2014 through July 2016, and were followed for up to 1 year by 48 clinicians in academic, community, Veterans Affairs, and military settings.
• Patients in the intervention group met with their clinicians and used a desktop interface to select treatments and trial parameters for an n-of-1 trial comparing two pain-management regimens.
• The mHealth app reminded participants to take their designated treatments on assigned days and to upload responses to daily questions on pain and treatment-associated adverse effects.
• Patients in the control group received care as usual in this analysis.
• Change in the Patient-Reported Outcomes Measurement Information System (PROMIS) pain-related interference eight-item, short-form scale (full scale range: 41-78) scores from baseline to 6 months was the primary outcome.
• Secondary outcomes included patient-reported pain intensity, overall health, analgesic adherence, trust in clinician, satisfaction with care, medication-related shared decision-making, and, for the n-of-1 group only, participant engagement and experience.

Results

• A total of 102 of 215 subjects (47%; n-of-1 intervention group, n=108; control group, n=107) were women.
• The mean (standard deviation) age was 55.5 (11.1) years.
• Pain interference was reduced in both groups, though there was no difference between the intervention and control groups (-1.36 points; 95% confidence interval [CI]: -2.91 to 0.19; P=0.09) at the 6-month follow-up.
• Except for higher medication-related shared decision-making at 6 months (between-group difference: 11.9 points; 95% CI: 2.6-21.2; P=0.01), there were no advantages in secondary outcomes for patients in the intervention group versus those in the control group.
• Of those in the n-of-1 group, 86 patients (88%) affirmed that the mHealth app could help people like them manage their pain.