title: mActive: A Randomized Clinical Trial of an Automated mHealth Intervention for Physical Activity Promotion.
abstract: BACKGROUND
  We hypothesized that a fully automated mobile health (mHealth) intervention with tracking and texting components would increase physical activity.
  
  
  RESULTS
  mActive enrolled smartphone users aged 18 to 69 years at an ambulatory cardiology center in Baltimore, Maryland. We used sequential randomization to evaluate the intervention's 2 core components. After establishing baseline activity during a blinded run-in (week 1), in phase I (weeks 2 to 3), we randomized 2:1 to unblinded versus blinded tracking. Unblinding allowed continuous access to activity data through a smartphone interface. In phase II (weeks 4 to 5), we randomized unblinded participants 1:1 to smart texts versus no texts. Smart texts provided smartphone-delivered coaching 3 times/day aimed at individual encouragement and fostering feedback loops by a fully automated, physician-written, theory-based algorithm using real-time activity data and 16 personal factors with a 10 000 steps/day goal. Forty-eight outpatients (46% women, 21% nonwhite) enrolled with a mean±SD age of 58±8 years, body mass index of 31±6 kg/m(2), and baseline activity of 9670±4350 steps/day. Daily activity data capture was 97.4%. The phase I change in activity was nonsignificantly higher in unblinded participants versus blinded controls by 1024 daily steps (95% confidence interval [CI], -580 to 2628; P=0.21). In phase II, participants receiving texts increased their daily steps over those not receiving texts by 2534 (95% CI, 1318 to 3750; P<0.001) and over blinded controls by 3376 (95% CI, 1951 to 4801; P<0.001).
  
  
  CONCLUSIONS
  An automated tracking-texting intervention increased physical activity with, but not without, the texting component. These results support new mHealth tracking technologies as facilitators in need of behavior change drivers.
  
  
  BACKGROUND
  URL: http://ClinicalTrials.gov/. Unique identifier: NCT01917812.
authors.affiliation: Ciccarone Center for the Prevention of Heart Disease, Johns Hopkins University School of Medicine, Baltimore, MD (S.S.M., D.I.F., R.S.B., S.R.J., W.S.P., R.A.M.K., E.D.M., C.E.N., E.V.R., M.J.B.) Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (S.S.M., W.S.P., R.A.M.K., E.D.M., C.E.N., J.C.).
authors.forename: Seth S
authors.initials: SS
authors.lastname: Martin
authors.affiliation: Ciccarone Center for the Prevention of Heart Disease, Johns Hopkins University School of Medicine, Baltimore, MD (S.S.M., D.I.F., R.S.B., S.R.J., W.S.P., R.A.M.K., E.D.M., C.E.N., E.V.R., M.J.B.).
authors.forename: David I
authors.initials: DI
authors.lastname: Feldman
authors.affiliation: Ciccarone Center for the Prevention of Heart Disease, Johns Hopkins University School of Medicine, Baltimore, MD (S.S.M., D.I.F., R.S.B., S.R.J., W.S.P., R.A.M.K., E.D.M., C.E.N., E.V.R., M.J.B.).
authors.forename: Roger S
authors.initials: RS
authors.lastname: Blumenthal
authors.affiliation: Ciccarone Center for the Prevention of Heart Disease, Johns Hopkins University School of Medicine, Baltimore, MD (S.S.M., D.I.F., R.S.B., S.R.J., W.S.P., R.A.M.K., E.D.M., C.E.N., E.V.R., M.J.B.).
authors.forename: Steven R
authors.initials: SR
authors.lastname: Jones
authors.affiliation: Ciccarone Center for the Prevention of Heart Disease, Johns Hopkins University School of Medicine, Baltimore, MD (S.S.M., D.I.F., R.S.B., S.R.J., W.S.P., R.A.M.K., E.D.M., C.E.N., E.V.R., M.J.B.) Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (S.S.M., W.S.P., R.A.M.K., E.D.M., C.E.N., J.C.).
authors.forename: Wendy S
authors.initials: WS
authors.lastname: Post
authors.affiliation: Ciccarone Center for the Prevention of Heart Disease, Johns Hopkins University School of Medicine, Baltimore, MD (S.S.M., D.I.F., R.S.B., S.R.J., W.S.P., R.A.M.K., E.D.M., C.E.N., E.V.R., M.J.B.) Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (S.S.M., W.S.P., R.A.M.K., E.D.M., C.E.N., J.C.).
authors.forename: Rebeccah A
authors.initials: RA
authors.lastname: McKibben
authors.affiliation: Ciccarone Center for the Prevention of Heart Disease, Johns Hopkins University School of Medicine, Baltimore, MD (S.S.M., D.I.F., R.S.B., S.R.J., W.S.P., R.A.M.K., E.D.M., C.E.N., E.V.R., M.J.B.) Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (S.S.M., W.S.P., R.A.M.K., E.D.M., C.E.N., J.C.).
authors.forename: Erin D
authors.initials: ED
authors.lastname: Michos
authors.affiliation: Ciccarone Center for the Prevention of Heart Disease, Johns Hopkins University School of Medicine, Baltimore, MD (S.S.M., D.I.F., R.S.B., S.R.J., W.S.P., R.A.M.K., E.D.M., C.E.N., E.V.R., M.J.B.) Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (S.S.M., W.S.P., R.A.M.K., E.D.M., C.E.N., J.C.).
authors.forename: Chiadi E
authors.initials: CE
authors.lastname: Ndumele
authors.affiliation: Ciccarone Center for the Prevention of Heart Disease, Johns Hopkins University School of Medicine, Baltimore, MD (S.S.M., D.I.F., R.S.B., S.R.J., W.S.P., R.A.M.K., E.D.M., C.E.N., E.V.R., M.J.B.).
authors.forename: Elizabeth V
authors.initials: EV
authors.lastname: Ratchford
authors.affiliation: Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (S.S.M., W.S.P., R.A.M.K., E.D.M., C.E.N., J.C.).
authors.forename: Josef
authors.initials: J
authors.lastname: Coresh
authors.affiliation: Ciccarone Center for the Prevention of Heart Disease, Johns Hopkins University School of Medicine, Baltimore, MD (S.S.M., D.I.F., R.S.B., S.R.J., W.S.P., R.A.M.K., E.D.M., C.E.N., E.V.R., M.J.B.).
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Blaha
mesh_terms: D056044:Actigraphy / Q000295:instrumentation*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000465:Algorithms; D001331:Automation; D015142:Baltimore; D002318:Cardiovascular Diseases / Q000175:diagnosis / Q000503:physiopathology / Q000517:prevention & control* / Q000523:psychology; D040421:Cell Phone; D003376:Counseling; D015444:Exercise; D005260:Female; D015438:Health Behavior; D007722:Health Knowledge, Attitudes, Practice; D006293:Health Promotion / Q000379:methods; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D063731:Mobile Applications; D009042:Motivation; D009043:Motor Activity; D010865:Pilot Projects; D012307:Risk Factors; D040242:Risk Reduction Behavior; D017216:Telemedicine / Q000295:instrumentation* / Q000379:methods; D060145:Text Messaging; D013997:Time Factors; D055815:Young Adult
keywords: accelerometer; activity tracker; automation; cardiovascular disease; digital health; eHealth; health technology; mHealth; mobile phone; pedometer; physical activity; prevention; smartphone; text messages; texting; wearable device; wearable sensor