Skip to main content

Table 5 Mapping equations from FIQR score to multi-attribute utility instruments

From: “Fibromyalgia and quality of life: mapping the revised fibromyalgia impact questionnaire to the preference-based instruments”

  AQoL-8D 15D EQ-5D-5 L SF-6D
Coeff. SE Coeff. SE Coeff. SE Coeff. SE
PANEL A
 OLS
  Constant .778 .027*** .997 .039*** 1.479 .024*** .794 .022***
  FIQR/100 −.564 .046*** −.420 .030***    −.383 .035***
  Age    −.001 .001*     
  Squared-FIQR      −.898 .056***   
 GLM
  Constant −.144 .060* .068 .058 .425 .025*** −.179 .039***
  FIQR/100 -1.175 .101*** −.600 .046***    −.670 .061***
  Age    −.002 .001*     
  Squared-FIQR      −.824 .058***   
PANEL B
 OLS
  Constant .787 .031*** .950 .021*** 1.496 .027*** .786 .025***
  Age         
  FIQR_D1    −.138 .036***    −.137 .043**
  FIQR_D2 −.144 .043**      −.089 .034**
  FIQR_D3 −.415 .065*** −.305 .042***    −.149 .049**
Squared FIQR_D1      −.335 .081***   
Squared FIQR_D2      −.167 .064**   
Squared FIQR_D3      −.415 .084***   
 GLM
  Constant −.132 .068* .078 .059 0.438 .028*** −.192 .044***
  Age    −.002 .001*     
  FIQR_D1    −.156 .058**    −.241 .075**
  FIQR_D2 −.318 .096** −.096 .048*    −.153 .059**
  FIQR_D3 −.840 .147*** −.359 .070***    −.264 .085**
Squared FIQR_D1      −.304 .081***   
Squared FIQ_D2      −.167 .065**   
Squared FIQR_D3      −.368 .086***   
  1. Coeff. and SE: Beta and Standard error of significant variables (*p < 0.05, **p < 0.01; ***p < 0.001) in the equations
  2. Panel A: FIQR, Squared-FIQR, Age
  3. Panel B: FIQR function domain (FIQR_D1); FIQR overall impact domain (FIQR_D2); FIQR symptom domain (FIQR_D2); Squared FIQR function domain; Squared FIQR overall impact domain; Squared FIQR symptom domain; Age
  4. Gamma GLM: Generalized linear model Gamma log-link. EQ-5D was pre-transformed as EQ-5D + 0.66 in order to calculate the Gamma GLM with all scores (including negative values). It was post-transformed as EQ-5D – 0.66
  5. Coefficients with best fitting for equations are in bold