title: What is the use? Application of the short form (SF) questionnaires for the evaluation of treatment effects.
abstract: BACKGROUND
  Health status has evolved as a clinical outcome measure that is of great interest in medical care. However, there is still debate about the appropriateness of scoring algorithms for the often used short form questionnaires. Therefore, our aim was to evaluate the consequences of the traditional scoring procedure based on orthogonal factor rotation for clinical applications by (a) re-evaluating the results of randomized controlled trials (RCTs) on the effectiveness of antidepressants in improving health status in cardiac patients and (b) comparing empirical evidence on depression and health status using orthogonal and oblique factor rotation (alternative scoring method) in a community sample and a heart failure (HF) sample.
  
  
  METHODS
  This is a systematic literature review and cross-sectional analysis among 1,598 community sample participants and 282 HF patients.
  
  
  RESULTS
  Orthogonal rotation artificially forces the mental component summary (MCS) and physical component summary (PCS) to be unrelated, which is illustrated in two of the three included RCTs. Two RCTs showed improvements in MCS, but no improvement in PCS over time. Cross-sectional analysis in the two datasets showed that employing the alternative scoring algorithm resulted in higher negative correlations of MCS and PCS with depression, and a gradual decline in MCS with each decile of decline in PCS.
  
  
  CONCLUSIONS
  Our data showed that appropriate carefulness is needed when calculating and interpreting summary scores. The traditional scoring algorithm seems inappropriate to objectively evaluate the effects of interventions on both the MCS and the PCS. Awareness in the design and evaluation of interventions using these outcomes is warranted.
authors.affiliation: Department of Medical Psychology & Clinical Psychology, Center of Research on Psychology in Somatic Diseases (CoRPS), Tilburg University, PO Box 90153, 5000, LE, Tilburg, The Netherlands.
authors.forename: Aline J
authors.initials: AJ
authors.lastname: Pelle
authors.forename: Nina
authors.initials: N
authors.lastname: Kupper
authors.forename: Floortje
authors.initials: F
authors.lastname: Mols
authors.forename: Peter
authors.initials: P
authors.lastname: de Jonge
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D000928:Antidepressive Agents / Q000009:adverse effects / Q000627:therapeutic use; D003430:Cross-Sectional Studies; D003863:Depression / Q000188:drug therapy / Q000523:psychology; D005163:Factor Analysis, Statistical; D005260:Female; D006304:Health Status; D006305:Health Status Indicators; D006306:Health Surveys; D006333:Heart Failure / Q000523:psychology* / Q000534:rehabilitation / Q000628:therapy; D006801:Humans; D008297:Male; D008603:Mental Health; D008875:Middle Aged; D009426:Netherlands; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data; D011159:Population Surveillance; D011594:Psychometrics; D011788:Quality of Life; D016032:Randomized Controlled Trials as Topic; D011795:Surveys and Questionnaires / Q000592:standards*
chemical_list: D000928:Antidepressive Agents