BioMed Central Page 1 of 13 (page number not for citation purposes) Health and Quality of Life Outcomes Open Access Research A new measure of patient satisfaction with ocular hypotensive medications: The Treatment Satisfaction Survey for Intraocular Pressure (TSS-IOP) Mark J Atkinson* 1 , William C Stewart 2 , Joel M Fain 3 , Jeanette A Stewart 4 , Ravinder Dhawan 3 , Essy Mozaffari 3 and Jan Lohs 5 Address: 1 Worldwide Outcomes Research, Pfizer, La Jolla, California, USA, 2 Pharmaceutical Research Network, Univ of S. Carolina School of Medicine, Charleston, South Carolina, USA, 3 Pfizer Global Pharmaceuticals, New York, NY, USA, 4 Clinical Project Management, Pharmaceutical Research Network, Charleston, South Carolina, USA and 5 Lohs Research Group, Palatine, Illinois, USA Email: Mark J Atkinson* - mark.j.atkinson@pfizer.com; William C Stewart - pr_wcs@bellsouth.net; Joel M Fain - joel.m.fain@pfizer.com; Jeanette A Stewart - pr_jas@bellsouth.net; Ravinder Dhawan - rdhawan@psmus.jnj.com; Essy Mozaffari - essy.mozaffari@pfizer.com; Jan Lohs - Lohsrsch@aol.com * Corresponding author Abstract Purpose: To validate the treatment-specific Treatment Satisfaction Survey for Intraocular Pressure (TSS- IOP). Methods: Item content was developed by 4 heterogeneous patient focus groups (n = 32). Instrument validation involved 250 patients on ocular hypotensive medications recruited from ophthalmology practices in the Southern USA. Participants responded to demographic and test questions during a clinic visit. Standard psychometric analyses were performed on the resulting data. Sample: Of the 412 patients screened, 253 consented to participate, and 250 provided complete datasets. The sample included 44% male (n = 109), 44% Black (n = 109) and 57% brown eyed (n = 142) participants, with a mean age of 64.6 years (SD 13.1) and a history of elevated IOP for an average of 8.4 yrs (SD 7.8). A majority was receiving monotherapy (60%, n = 151). Results: A PC Factor analysis (w/ varimax rotation) of the 31 items yielded 5 factors (Eigenvalues > 1.0) explaining 70% of the total variance. Weaker and conceptually redundant items were removed and the remaining 15 items reanalyzed. The satisfaction factors were; Eye Irritation (EI; 4 items), Convenience of Use (CofU; 3 items), Ease of Use (EofU; 3 items), Hyperemia (HYP; 3 items), and Medication Effectiveness (EFF; 2 items). Chronbach's Alphas ranged from .80 to .86. Greater distributional skew was found for less common experiences (i.e., HYP & EI with 65% & 48.4% ceilings) than for more common experiences (i.e., EofU, CofU, EFF with 10.8%, 20.8% & 15.9% ceilings). TSS-IOP scales converged with conceptually related scales on a previously validated measure of treatment satisfaction, the TSQM (r = .36 to .77). Evidence of concurrent criterion-related validity was found. Patients' symptomatic ratings of eye irritation, hyperemia and difficulties using the medication correlated with satisfaction on these dimensions (r = .30-.56, all p < .001). Clinicians' ratings of IOP control, severity of side effects and problematic medication use correlated with patients' satisfaction scores on these dimensions (r = .13-.26, all p < .01). Conclusions: This study provides initial evidence that the TSS-IOP is a reliable and valid measure, assessing patients' satisfaction with ocular hypotensive medications. Published: 15 November 2003 Health and Quality of Life Outcomes 2003, 1:67 Received: 02 September 2003 Accepted: 15 November 2003 This article is available from: http://www.hqlo.com/content/1/1/67 © 2003 Atkinson et al; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL.