title: Quantifying Barriers to Improvement of Treatment Satisfaction in Men With Erectile Dysfunction: Use of Person-Item Maps.
abstract: Patient-reported outcomes are a valuable tool used to gauge treatment satisfaction in different conditions, including erectile dysfunction (ED).
  
  
  
  To use person-item maps to quantify barriers to improvement of treatment satisfaction in men with ED.
  
  
  
  Men 18 to 65 years old with documented ED received sildenafil 50 mg, sildenafil 100 mg, or placebo for 8 weeks in a double-blinded manner. Post hoc analyses were conducted on Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) data (11 items rating treatment satisfaction; each item score range = 0-4).
  
  
  
  Person-item maps were developed based on Rasch models. To quantify barriers to improvement of treatment satisfaction, responses to the 11 items of the EDITS questionnaire were dichotomized to indicate improvement (responses of 3 or 4 were combined to a score of 1) vs no change or worsening (responses of 0, 1, or 2 were combined to a score of 0).
  
  
  
  Analyses were conducted using data from 278 men who completed the EDITS questionnaire at the end of double-blinded treatment. The person-item map indicated that EDITS item 4 (ease of use of treatment) was the easiest barrier to overcome, whereas the most difficult barrier to improvement of treatment satisfaction was EDITS item 2 (degree to which treatment met expectations). Most men in the sildenafil 100-mg group endorsed most EDITS items, consistent with substantial improvement. The sildenafil 50-mg group was similar, but with smaller frequencies for endorsing improvement of the more difficult EDITS items. In contrast, men receiving placebo endorsed mainly the easiest EDITS items, with only a small number of men endorsing the difficult items.
  
  
  
  A person-item map is a useful means for quantifying barriers to improvement of treatment satisfaction represented by EDITS items in patients with ED.
authors.affiliation: Pfizer Inc, Groton, CT, USA.
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Bushmakin
authors.affiliation: Pfizer Inc, Groton, CT, USA. Electronic address: joseph.c.cappelleri@pfizer.com.
authors.forename: Joseph C
authors.initials: JC
authors.lastname: Cappelleri
authors.affiliation: Pfizer, Inc, New York, NY, USA.
authors.forename: Vera
authors.initials: V
authors.lastname: Stecher
authors.affiliation: Department of Urology, University of California-San Francisco, San Francisco, CA, USA.
authors.forename: Tom F
authors.initials: TF
authors.lastname: Lue
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004311:Double-Blind Method; D007172:Erectile Dysfunction / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D000068677:Sildenafil Citrate / Q000627:therapeutic use*; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: D000068677:Sildenafil Citrate
keywords: Erectile Dysfunction; Patient-Reported Outcomes; Person-Item Map; Rasch Model; Sildenafil; Treatment Satisfaction