Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí hóa học đề tài : Interpretation of response categories in patient-reported rating scales: a controlled study among people with Parkinson's disease | Knutsson et al. Health and Quality of Life Outcomes 2010 8 61 http content 8 1 61 I HEALTH AND QUALITY OF LIFE OUTCOMES RESEARCH Open Access Interpretation of response categories in patient-reported rating scales a controlled study among people with Parkinson s disease Ida Knutsson 1 Helena Rydstrom1 Jan Reimer2 Per Nyberg1 and Peter Hagell 1 2 Abstract Background Unambiguous interpretation of ordered rating scale response categories requires distinct meanings of category labels. Also summation of item responses into total scores assumes equal intervals between categories. While studies have identified problems with rating scale response category functioning there is a paucity of empirical studies regarding how respondents interpret response categories. We investigated the interpretation of commonly used rating scale response categories and attempted to identify distinct and roughly equally spaced response categories for patient-reported rating scales in Parkinson s disease PD and age-matched control subjects. Methods Twenty-one rating scale response categories representing frequency intensity and level of agreement were presented in random order to 51 people with PD 36 men mean age 66 years and 36 age-matched controls 14 men mean age 66 . Respondents indicated their interpretation of each category on 100-mm visual analog scales VAS anchored by Never - Always Not at all - Extremely and Totally disagree - Completely agree. VAS values were compared between groups and response categories with mean values and non-overlapping 95 CIs corresponding to equally spaced locations on the VAS line were sought to identify the best options for three- four- five- and six-category scales. Results VAS values did not differ between the PD and control samples P or according to educational level P age P self-reported physical functioning P and mental health P or for the PD sample PD duration P or presence of dyskinesias P . .
