title: Association of online patient access to clinicians and medical records with use of clinical services.
abstract: BACKGROUND
  Prior studies suggest that providing patients with online access to health records and e-mail communication with physicians may substitute for traditional health care services.
  
  
  OBJECTIVE
  To assess health care utilization by both users and nonusers of online access to health records before and after initiation of MyHealthManager (MHM), a patient online access system.
  
  
  METHODS
  Retrospective cohort study of the use of health care services by members (≥18 years old) who were continuously enrolled for at least 24 months during the study period March 2005 through June 2010 in Kaiser Permanente Colorado, a group model, integrated health care delivery system. Propensity scores (using age, sex, utilization frequencies, and chronic illnesses) were used for cohort matching. Unadjusted utilization rates were calculated for both MHM users and nonusers and were the basis for difference-of-differences analyses. We also used generalized estimating equations to compare the adjusted rates of utilization of health care services before and after online access.
  
  
  METHODS
  Rates of office visits, telephone encounters, after-hours clinic visits, emergency department encounters, and hospitalizations between members with and without online access.
  
  
  RESULTS
  Comparing the unadjusted rates for use of clinical services before and after the index date between the matched cohorts, there was a significant increase in the per-member rates of office visits (0.7 per member per year; 95% CI, 0.6-0.7; P < .001) and telephone encounters (0.3 per member per year; 95% CI, 0.2-0.3; P < .001). There was also a significant increase in per-1000-member rates of after-hours clinic visits (18.7 per 1000 members per year; 95% CI, 12.8-24.3; P < .001), emergency department encounters (11.2 per 1000 members per year; 95% CI, 2.6-19.7; P = .01), and hospitalizations (19.9 per 1000 members per year; 95% CI, 14.6-25.3; P < .001) for MHM users vs nonusers.
  
  
  CONCLUSIONS
  Having online access to medical records and clinicians was associated with increased use of clinical services compared with group members who did not have online access.
authors.affiliation: Institute for Health Research, Kaiser Permanente Colorado, 10065 E Harvard Ave, Ste 300, Denver, CO 80231, USA. ted.e.palen@kp.org
authors.forename: Ted E
authors.initials: TE
authors.lastname: Palen
authors.forename: Colleen
authors.initials: C
authors.lastname: Ross
authors.forename: J David
authors.initials: JD
authors.lastname: Powers
authors.forename: Stanley
authors.initials: S
authors.lastname: Xu
mesh_terms: D022126:Access to Information; D000328:Adult; D039602:After-Hours Care / Q000706:statistics & numerical data; D015331:Cohort Studies; D003120:Colorado; D057286:Electronic Health Records / Q000706:statistics & numerical data*; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D005260:Female; D006279:Health Maintenance Organizations; D006296:Health Services / Q000706:statistics & numerical data*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D020407:Internet; D008297:Male; D008875:Middle Aged; D009819:Office Visits / Q000706:statistics & numerical data; D012189:Retrospective Studies; D013689:Telephone; D055815:Young Adult