OBJECTIVES: To compare different approaches to address ceiling effects when predicting EQ-5D index scores from the 10 subscales of the MOS-HIV Health Survey. STUDY DESIGN: Data were collected from an HIV treatment trial. Statistical methods included ordinary least squares (OLS) regression, the censored least absolute deviations (CLAD) approach, a standard two-part model (TPM), a TPM with a log-transformed EQ-5D index, and a latent class model (LCM). Predictive accuracy was evaluated using percentage of absolute error (R(1)) and squared error (R(2)) predicted by statistical methods. FINDINGS: A TPM with a log-transformed EQ-5D index performed best on R(1); a LCM performed best on R(2). In contrast, the CLAD was worst. Performance of the OLS and a standard TPM were intermediate. Values for R(1) ranged from 0.33 (CLAD) to 0.42 (TPM-L); R(2) ranged from 0.37 (CLAD) to 0.53 (LCM). CONCLUSIONS: The LCM and TPM with a log-transformed dependent variable are superior to other approaches in handling data with ceiling effects.
RCT Entities:
OBJECTIVES: To compare different approaches to address ceiling effects when predicting EQ-5D index scores from the 10 subscales of the MOS-HIV Health Survey. STUDY DESIGN: Data were collected from an HIV treatment trial. Statistical methods included ordinary least squares (OLS) regression, the censored least absolute deviations (CLAD) approach, a standard two-part model (TPM), a TPM with a log-transformed EQ-5D index, and a latent class model (LCM). Predictive accuracy was evaluated using percentage of absolute error (R(1)) and squared error (R(2)) predicted by statistical methods. FINDINGS: A TPM with a log-transformed EQ-5D index performed best on R(1); a LCM performed best on R(2). In contrast, the CLAD was worst. Performance of the OLS and a standard TPM were intermediate. Values for R(1) ranged from 0.33 (CLAD) to 0.42 (TPM-L); R(2) ranged from 0.37 (CLAD) to 0.53 (LCM). CONCLUSIONS: The LCM and TPM with a log-transformed dependent variable are superior to other approaches in handling data with ceiling effects.
Authors: Peter Franks; Erica I Lubetkin; Marthe R Gold; Daniel J Tancredi; Haomiao Jia Journal: Med Decis Making Date: 2004 May-Jun Impact factor: 2.583
Authors: Nalin Payakachat; Kent H Summers; Andreas M Pleil; Matthew M Murawski; Joseph Thomas; Kristofer Jennings; James G Anderson Journal: Qual Life Res Date: 2009-06-19 Impact factor: 4.147
Authors: Yin Bun Cheung; Hui Xing Tan; Vivian Wei Wang; Nagaendran Kandiah; Nan Luo; Gerald C H Koh; Hwee Lin Wee Journal: Qual Life Res Date: 2018-09-01 Impact factor: 4.147