title: Computerized health information and the demand for medical care.
abstract: OBJECTIVE
  Consumer health information, once the domain of books and booklets, has become increasingly digitized and available on the Internet. This study assessed the effect of using computerized health information on consumers' demand for medical care.
  
  
  METHODS
  The dependent variable was self-reported number of visits to the doctor in the past year. The key independent variable was the use of computerized health information, which was treated as endogenous. We tested the effect of using computerized health information on physician visits using ordinary least squares, instrumental variables, fixed effects, and fixed-effects instrumental variables models. The instrumental variables included exposure to the Healthwise Communities Project, a community-wide health information intervention; computer ownership; and Internet access. Random households in three cities were mailed questionnaires before and after the Healthwise Communities Project. In total, 5909 surveys were collected for a response rate of 54%.
  
  
  RESULTS
  In both the bivariate and the multivariate analyses, the use of computerized health information was not associated with self-reported entry into care or number of visits. The instrumental variables models also found no differences, with the exception that the probability of entering care was significantly greater with the two-stage conditional logit model (P <.05).
  
  
  CONCLUSIONS
  Although providing people with health information is intuitively appealing, we found little evidence of an association between using a computer for health information and self-reported medical visits in the past year. This study used overall self-reported utilizations as the dependent variable, and more research is needed to determine whether health information affects the health production function in other important ways, such as the location of care, the timing of getting care, or the intensity of treatment.
authors.affiliation: VA Health Economics Resource Center, Palo Alto Medical Center, Palo Alto, CA, USA. twagner@stanford.edu
authors.forename: Todd H
authors.initials: TH
authors.lastname: Wagner
authors.forename: Holly B
authors.initials: HB
authors.lastname: Jimison
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D003153:Community Health Services / Q000458:organization & administration; D005260:Female; D019538:Health Care Surveys; D006300:Health Services Misuse / Q000706:statistics & numerical data; D015277:Hotlines / Q000458:organization & administration; D006801:Humans; D007061:Idaho; D007255:Information Services / Q000706:statistics & numerical data*; D020407:Internet / Q000706:statistics & numerical data*; D016018:Least-Squares Analysis; D016015:Logistic Models; D016239:MEDLINE / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D009009:Montana; D009819:Office Visits / Q000706:statistics & numerical data*; D009922:Oregon; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data*; D015397:Program Evaluation; D012648:Self Care; D011795:Surveys and Questionnaires