%0 Journal Article
%@ 2291-5222
%I JMIR Publications
%V 5
%N 11
%P e168
%T Recruitment and Ongoing Engagement in a UK Smartphone Study Examining the Association Between Weather and Pain: Cohort Study
%A Druce,Katie L
%A McBeth,John
%A van der Veer,Sabine N
%A Selby,David A
%A Vidgen,Bertie
%A Georgatzis,Konstantinos
%A Hellman,Bruce
%A Lakshminarayana,Rashmi
%A Chowdhury,Afiqul
%A Schultz,David M
%A Sanders,Caroline
%A Sergeant,Jamie C
%A Dixon,William G
%+ Arthritis Research UK Centre for Epidemiology, University of Manchester, Stopford Building, Oxford Road, Manchester, M13 9PT, United Kingdom, 44 161 275 1604, katie.druce@manchester.ac.uk
%K epidemiology
%K mHealth
%K chronic pain
%K methods
%D 2017
%7 01.11.2017
%9 Original Paper
%J JMIR Mhealth Uhealth
%G English
%X Background: The huge increase in smartphone use heralds an enormous opportunity for epidemiology research, but there is limited evidence regarding long-term engagement and attrition in mobile health (mHealth) studies. Objective: The objective of this study was to examine how representative the Cloudy with a Chance of Pain study population is of wider chronic-pain populations and to explore patterns of engagement among participants during the first 6 months of the study. Methods: Participants in the United Kingdom who had chronic pain (≥3 months) and enrolled between January 20, 2016 and January 29, 2016 were eligible if they were aged ≥17 years and used the study app to report any of 10 pain-related symptoms during the study period. Participant characteristics were compared with data from the Health Survey for England (HSE) 2011. Distinct clusters of engagement over time were determined using first-order hidden Markov models, and participant characteristics were compared between the clusters. Results: Compared with the data from the HSE, our sample comprised a higher proportion of women (80.51%, 5129/6370 vs 55.61%, 4782/8599) and fewer persons at the extremes of age (16-34 and 75+). Four clusters of engagement were identified: high (13.60%, 865/6370), moderate (21.76%, 1384/6370), low (39.35%, 2503/6370), and tourists (25.44%, 1618/6370), between which median days of data entry ranged from 1 (interquartile range; IQR: 1-1; tourist) to 149 (124-163; high). Those in the high-engagement cluster were typically older, whereas those in the tourist cluster were mostly male. Few other differences distinguished the clusters. Conclusions: Cloudy with a Chance of Pain demonstrates a rapid and successful recruitment of a large, representative, and engaged sample of people with chronic pain and provides strong evidence to suggest that smartphones could provide a viable alternative to traditional data collection methods. 
%M 29092810
%R 10.2196/mhealth.8162
%U http://mhealth.jmir.org/2017/11/e168/
%U https://doi.org/10.2196/mhealth.8162
%U http://www.ncbi.nlm.nih.gov/pubmed/29092810