Effect of mode of administration on I-PSS scores in a large BPH patient population.
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.
Garcia-Losa
M
M
SmithKline Beecham Pharmaceuticals, Madrid, Spain.
Unda
M
M
Badia
X
X
Rodriguez-Alcantara
F
F
Carballido
J
J
Dal-Ré
R
R
Herdman
M
M
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