PURPOSE: We explore the impact of study designs, biases, outcome variables and statistical techniques when interpreting studies concerning prostate cancer management. MATERIALS AND METHODS: Examples from the current literature and a recently assembled population based sample of patients 55 to 75 years old at diagnosis identified by the Connecticut Tumor Registry as having newly diagnosed localized prostate cancer between 1971 and 1984 are provided to assist the reader to understand the principles discussed. RESULTS: Most reports concerning prostate cancer outcomes suffer from obvious and subtle biases that confound the reader's understanding of the impact of different treatment alternatives. CONCLUSIONS: By remaining vigilant to these confounding issues, clinicians and patients can gain greater insights into the medical literature and can make individual interpretations concerning the potential impact of treatment interventions on men with prostate cancer.
PURPOSE: We explore the impact of study designs, biases, outcome variables and statistical techniques when interpreting studies concerning prostate cancer management. MATERIALS AND METHODS: Examples from the current literature and a recently assembled population based sample of patients 55 to 75 years old at diagnosis identified by the Connecticut Tumor Registry as having newly diagnosed localized prostate cancer between 1971 and 1984 are provided to assist the reader to understand the principles discussed. RESULTS: Most reports concerning prostate cancer outcomes suffer from obvious and subtle biases that confound the reader's understanding of the impact of different treatment alternatives. CONCLUSIONS: By remaining vigilant to these confounding issues, clinicians and patients can gain greater insights into the medical literature and can make individual interpretations concerning the potential impact of treatment interventions on men with prostate cancer.