title: When to combine hypotheses and adjust for multiple tests.
abstract: OBJECTIVE
  To provide guidelines for identifying composite hypotheses and addressing the probability of false rejection for multiple hypotheses.
  
  
  METHODS
  Examples from the literature in health services research are used to motivate the discussion of composite hypothesis tests and multiple hypotheses.
  
  
  METHODS
  This article is a didactic presentation.
  
  
  RESULTS
  It is not rare to find mistaken inferences in health services research because of inattention to appropriate hypothesis generation and multiple hypotheses testing. Guidelines are presented to help researchers identify composite hypotheses and set significance levels to account for multiple tests.
  
  
  CONCLUSIONS
  It is important for the quality of scholarship that inferences are valid: properly identifying composite hypotheses and accounting for multiple tests provides some assurance in this regard.
authors.affiliation: Department of Community and Preventive Medicine, University of Rochester, 601 Elmwood Ave., Box 644, Rochester, NY 14642, USA.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Veazie
mesh_terms: D015982:Bias; D017408:Guidelines as Topic; D006302:Health Services Research / Q000379:methods* / Q000592:standards; D011786:Quality Control; D014481:United States