Separating gains and losses in health when calculating the minimum important difference for mapped utility measures

Abstract

Researchers should consider the effects of combining gains and losses when determining utility MID values.

Six-Minute-Walk Test in Idiopathic Pulmonary Fibrosis

“…Effect size was calculated by dividing the difference in 6MWD values at baseline and Week 48 by the estimated standard deviation at baseline. A change in value corresponding to a ''small'' effect size was considered to approximate the MCID (21,31,32). One-third of the estimated standard deviation has also been suggested as an approximation of MCID (33).…”

The minimal important difference of the epistaxis severity score in hereditary hemorrhagic telangiectasia

“…The minimal important difference (MID) offers the best way to interpret and describe significant changes in HR‐QoL. The MID is defined as the smallest difference in outcome measurement that is large enough to have an implication for the patient's treatment or care . Many past studies have used the MID to add greater clinical meaning to outcome measurements.…”

“…The MID is defined as the smallest difference in outcome measurement that is large enough to have an implication for the patient's treatment or care. 10 Many past studies have used the MID to add greater clinical meaning to outcome measurements. Minimal important differences have been calculated for acute otitis media severity, the 6minute walk test for pulmonary arterial hypertension, and the BREAST-Q score for breast surgery.…”

Effectiveness and cost-effectiveness of sentinel lymph node biopsy compared with axillary node dissection in patients with early-stage breast cancer: a decision model analysis

“…The disutility value of 0.03 has been defined as the smallest difference in utility that is considered to be clinically important (Nichol and Epstein, 2008), and in the context of our model, implies that patients would equate 10 years of life with moderate–severe lymphoedema to 9.7 years of life in full health. In contrast, for patients at high risk of axillary metastases, ALND was more effective than SLNB at a disutility for lymphoedema at 0.03.…”

“…As we did not find any published data on the utility of breast cancer patients with lymphoedema, a ‘disutility' (quality-of-life decrement) was applied to patients with moderate-severe lymphoedema. This disutility was conservatively assumed to be 0.03 in the base-case analysis, which has been defined as the smallest clinically important difference in utility (Nichol and Epstein, 2008). A range of 0.01 to 0.05 was tested in the sensitivity analysis to reflect the uncertainty surrounding this estimate.…”