Baseline comparison of three health utility measures and the feeling thermometer among participants in the Action to Control Cardiovascular Risk in Diabetes trial.
ABSTRACT Health utility (HU) measures are used as overall measures of quality of life and to determine quality adjusted life years (QALYs) in economic analyses. We compared baseline values of three HUs including Short Form 6 Dimensions (SF-6D), and Health Utilities Index, Mark II and Mark III (HUI2 and HUI3) and the feeling thermometer (FT) among type 2 diabetes participants in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. We assessed relationships between HU and FT values and patient demographics and clinical variables.
ACCORD was a randomized clinical trial to test if intensive controls of glucose, blood pressure and lipids can reduce the risk of major cardiovascular disease (CVD) events in type 2 diabetes patients with high risk of CVD. The health-related quality of life (HRQOL) sub-study includes 2,053 randomly selected participants. Interclass correlations (ICCs) and agreement between measures by quartile were used to evaluate relationships between HU's and the FT. Multivariable regression models specified relationships between patient variables and each HU and the FT.
The ICCs were 0.245 for FT/SF-6D, 0.313 for HUI3/SF-6D, 0.437 for HUI2/SF-6D, 0.338 for FT/HUI2, 0.337 for FT/HUI3 and 0.751 for HUI2/HUI3 (P < 0.001 for all). Common classification by quartile was found for the majority (62%) of values between HUI2 and HUI3, which was significantly (P < 0.001) higher than between other HUs and the FT: SF-6D/HUI3 = 40.8%, SF-6D/HUI2 = 40.9%, FT/HUI3 = 35.0%, FT/HUI2 = 34.9%, and FT/SF-6D = 31.9%. Common classification was higher between SF-6D/HUI2 and SF-6D/HUI3 (P < 0.001) than between FT/SF-6D, FT/HUI2, and FT/HUI3. The mean difference in HU values per patient ranged from -0.024 ± 0.225 for SF-6D/ HUI3 to -0.124 ± 0.133 for SF-6D/HUI2. Regression models were significant; clinical and demographic variables explained 6.1% (SF-6D) to 7.7% (HUI3) of the variance in HUs.
The agreements between the different HUs were poor except for the two HUI measures; therefore HU values derived different measures may not be comparable. The FT had low agreement with HUs. The relationships between HUs and demographic and clinical measures demonstrate how severity of diabetes and other clinical and demographic factors are associated with HUs and FT measures.
ClinicalTrials.gov Identifier: NCT00000620.
Full-textDOI: · Available from: K M V Narayan, Jun 22, 2015
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ABSTRACT: BACKGROUND: A variety of instruments are used to measure health related quality of life. Few data exist on the performance and agreement of different instruments in a depressed population. The aim of this study was to investigate agreement between, and suitability of, the EQ-5D-3L, EQ-5D Visual Analogue Scale (EQ-5D VAS), SF-6D and SF-12 new algorithm for measuring health utility in depressed patients. METHODS: The intraclass correlation coefficient (ICC) and Bland and Altman approaches were used to assess agreement. Instrument sensitivity was analysed by: (1) plotting utility scores for the instruments against one another; (2) correlating utility scores and depressive symptoms (Beck Depression Inventory (BDI)); and (3) using Tukey's procedure. Receiver Operating Characteristic (ROC) analysis assessed instrument responsiveness to change. Acceptability was assessed by comparing instrument completion rates. RESULTS: The overall ICC was 0.57. Bland and Altman plots showed wide limits of agreement for each pair wise comparison, except between the SF-6D and SF-12 new algorithm. Plots of utility scores displayed 'ceiling effects' in the EQ-5D-3L index and 'floor effects' in the SF-6D and SF-12 new algorithm. All instruments showed a negative monotonic relationship with BDI, but the EQ-5D-3L index and EQ-5D VAS could not differentiate between depression severity sub-groups. The SF-based instruments were better able to detect changes in health state over time. There was no difference in completion rates of the four instruments. CONCLUSIONS: There was a lack of agreement between utility scores generated by the different instruments. According to the criteria of sensitivity, responsiveness and acceptability that we applied, the SF-6D and SF-12 may be more suitable for the measurement of health related utility in a depressed population than the EQ-5D-3L, which is the instrument currently recommended by NICE.Health and Quality of Life Outcomes 05/2013; 11(1):81. DOI:10.1186/1477-7525-11-81 · 2.10 Impact Factor
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ABSTRACT: BACKGROUND: We developed preference-based and summated scale scoring for the Testing Morbidities Index (TMI) classification, which addresses short-term effects on quality of life from diagnostic testing before, during, and after testing procedures. METHODS: The two TMI preference functions use multiattribute value techniques; one is patient-based and the other has a societal perspective, informed by 206 breast biopsy patients and 466 (societal) subjects. Because of a lack of standard short-term methods for this application, we used the visual analog scale (VAS). Waiting tradeoff (WTO) tolls provided an additional option for linear transformation of the TMI. We randomized participants to 1 of 3 surveys: The first derived weights for generic testing morbidity attributes and levels of severity with the VAS; a second developed VAS values and WTO tolls for linear transformation of the TMI to a "dead-healthy" scale; the third addressed initial validation in a specific test (breast biopsy). The initial validation included 188 patients and 425 community subjects. Direct VAS and WTO values were compared with the TMI. Alternative TMI scoring as a nonpreference summated scale was included, given evidence of construct and content validity. RESULTS: The patient model can use an additive function, whereas the societal model is multiplicative. Direct VAS and the VAS-scaled TMI were correlated across modeling groups (r = 0.45-0.62). Agreement was comparable to the value function validation of the Health Utilities Index 2. Mean absolute difference (MAD) calculations showed a range of 0.07-0.10 in patients and 0.11-0.17 in subjects. MAD for direct WTO tolls compared with the WTO-scaled TMI varied closely around 1 quality-adjusted life day. CONCLUSIONS: The TMI shows initial promise in measuring short-term testing-related health states.Medical Decision Making 05/2013; 33(6). DOI:10.1177/0272989X13487605 · 2.27 Impact Factor