Are the Effects of Gambling Treatment Overestimated?

  • James R. Westphal



Studies of clinical trials across the field of healthcare found use of designs that overestimate treatment effects.


review clinical trial designs used to develop gambling treatment evidence base for suitability to assess cause and effect and to accurately assess treatment effects.


literature review, grading of evidence, proportions and confidence limits


The majority of published studies on gambling treatment are methodologically unsuited to determine treatment effects. Suitable (randomized and controlled) trails often use designs that can overestimate treatment effects. Attrition in published studies of gambling treatment is substantial, ranging from 11 to 83%. If attrition is not included in the analysis, overestimation of treatment effects may be similar in magnitude.


The current evidence may overestimate gambling treatment effects. The inclusion of intention to treat analysis, careful blinding, more equivalent control groups and measures of adherence to treatment would improve problem gambling treatment clinical trial design.


Problem gambling treatment Problem gambling treatment retention Evaluation of evidence for problem gambling treatment 


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Copyright information

© Springer Verlag 2006

Authors and Affiliations

  1. 1.Department of PsychiatryUniversity of Hawaii at ManoaHonoluluUSA
  2. 2.John Burns School of MedicineUniversity of Hawaii at ManoaHonoluluUSA
  3. 3.Hawaii State HospitalKaneoheUSA

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