Goin J E, Olaleye D, Peters K M, Steinert B, Habicht K, Wynant G
DataMedix Corporation, Wayne, Pennsylvania, USA.
J Urol. 1998 Mar;159(3):1085-90.
A psychometric analysis of the University of Wisconsin Interstitial Cystitis Scale was conducted on 30 females previously enrolled in a phase II double-blind randomized controlled trial evaluating the efficacy of six weekly intravesical instillations of TICE BCG. The analyses were to: (1) evaluate the adequacy of the seven individual IC component items for measuring the range of patient responses; (2) verify the 2-factor (IC versus reference) construct of the scale; (3) evaluate the internal consistency and reliability of the IC items; (4) better define the scale's applicability and limitations; and (5) if possible, make recommendations for improvements in the scale.
Standard psychometric analyses were used to perform the evaluation, and included descriptive analysis of individual items, computing of item-total correlations and Cronbach's internal consistency measures, and the application of factor and Rasch analyses.
The original 7-item IC scale was found to have ceiling effects that could limit its use in detecting small therapeutic differences. It was also found that the Pelvic item originally assigned to the reference set of items of the scale should be included as an IC item when used in a comparable IC population. After including this item into the IC scale Cronbach's alpha was 0.84, compared with 0.82.
The UW-IC Scale has psychometric properties similar to other measurement instruments used in clinical research, and appears worthy of further study in well-characterized IC populations. The reference items suggest that IC patients do not indiscriminately report high values for generalized body complaints, but do so on bladder related symptoms as recorded by the IC items of the scale. Although the scale has limitations it appears applicable for use in future IC intervention clinical trials.
对威斯康星大学间质性膀胱炎量表进行心理测量分析，该分析针对30名女性进行，这些女性先前参加了一项II期双盲随机对照试验，评估每周六次膀胱内灌注卡介苗（TICE BCG）的疗效。分析旨在：（1）评估七个单独的间质性膀胱炎（IC）分量表项目对于测量患者反应范围的充分性；（2）验证量表的双因素（IC与对照）结构；（3）评估IC项目的内部一致性和可靠性；（4）更好地界定量表的适用性和局限性；（5）如有可能，对量表的改进提出建议。
采用标准心理测量分析进行评估，包括对单个项目的描述性分析、计算项目与总分的相关性以及克朗巴哈内部一致性测量，以及应用因素分析和拉施分析。
发现最初的7项IC量表存在天花板效应，这可能限制其在检测微小治疗差异方面的应用。还发现，量表中最初分配到对照项目组的盆腔项目，在用于类似的IC人群时应作为IC项目纳入。将该项目纳入IC量表后，克朗巴哈α系数为0.84，之前为0.82。
UW-IC量表具有与临床研究中使用的其他测量工具相似的心理测量特性，似乎值得在特征明确的IC人群中进一步研究。对照项目表明，IC患者并非不加区分地对全身一般性不适报告高分，而是对量表中IC项目所记录的膀胱相关症状报告高分。尽管该量表有局限性，但似乎适用于未来的IC干预临床试验。
