Responsiveness of the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI)

Qual Life Res. 2006 Mar;15(2):299-305. doi: 10.1007/s11136-005-1317-1.


Objectives: The NIH-Chronic Prostatitis Symptom Index (NIH-CPSI) was developed to assess symptoms and quality of life in men with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). We assessed the responsiveness of the NIH-CPSI to change over time and defined thresholds for changes perceptible to patients.

Methods: We studied 174 men with CP/CPPS who participated in a placebo-controlled randomized clinical trial. Changes from baseline to six weeks in the NIH-CPSI total score and pain, urinary, and quality of life subscores were compared to a global response assessment (GRA). Effect sizes and Guyatt statistics were calculated to evaluate responsiveness; 95% confidence intervals were produced using bootstrapping.

Results: All scores decreased over time with the largest decrease in subjects who reported on the GRA that they were markedly improved. The NIH-CPSI total, pain, and quality of life scores were highly responsive in the improved groups; the urinary score showed minimal responsiveness. There was no evidence of responsiveness among those subjects who worsened on the trial. ROC curves identified a 6-point decline in the NIH-CPSI total score as the optimal threshold to predict treatment response.

Conclusions: The NIH-CPSI total score and pain and quality of life subscores are responsive to change over time.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Validation Study

MeSH terms

  • Adult
  • Chronic Disease
  • Humans
  • Male
  • Middle Aged
  • National Institutes of Health (U.S.)*
  • Pain Measurement*
  • Prostatitis / physiopathology*
  • Quality of Life
  • Surveys and Questionnaires*
  • United States