title: Effect of mode of administration on I-PSS scores in a large BPH patient population.
abstract: OBJECTIVE
  The International Prostate Symptoms Score (I-PSS) was designed to be self-administered to patients with benign prostatic hyperplasia. This study tested for a possible mode of administration effect on the I-PSS and assessed the reliability of the I-PSS over time when modes of administration varied.
  
  
  METHODS
  Benign prostatic hyperplasia patients over 50 years of age were recruited at 52 Spanish centres. The I-PSS was administered on two occasions 1 month apart. Patients were sequentially classified into groups A-D according to the mode of administration (S = self-administered, I = interview administered) at the two visits (A = S-S, B = S-I, C = I-S, and D = I-I). The intraclass correlation coefficient was used to assess test-retest reliability, and multiple regression analysis was used to test the effects of the mode of administration and the visit number on I-PSS scores.
  
  
  RESULTS
  926 patients (mean age 66 years) were evaluated. The mean I-PSSs symptoms score at visit 1 in groups A-D were, respectively, 13.19, 13.57, 12.06, and 12.29. Multiple regression analysis between-group scores were 0.93 points higher when the I-PSS was self-administered and 1.98 points lower at the second visit. The intraclass correlation coefficients were: group A = 0.77, group B = 0.70, group C = 0.67, and group D = 0.76.
  
  
  CONCLUSIONS
  Interview administration of the I-PSS results in slightly lower scores. The reliability is higher when the same mode of administration is used at two recurrent visits.
authors.affiliation: SmithKline Beecham Pharmaceuticals, Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Garcia-Losa
authors.forename: M
authors.initials: M
authors.lastname: Unda
authors.forename: X
authors.initials: X
authors.lastname: Badia
authors.forename: F
authors.initials: F
authors.lastname: Rodriguez-Alcantara
authors.forename: J
authors.initials: J
authors.lastname: Carballido
authors.forename: R
authors.initials: R
authors.lastname: Dal-Ré
authors.forename: M
authors.initials: M
authors.lastname: Herdman
mesh_terms: D000367:Age Factors; D000368:Aged; D004522:Educational Status; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D011470:Prostatic Hyperplasia / Q000145:classification* / Q000175:diagnosis; D011788:Quality of Life; D012044:Regression Analysis; D015203:Reproducibility of Results; D018401:Sample Size; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D013997:Time Factors