TY - JOUR
T1 - Three ways to quantify uncertainty in individually applied "minimal important change" values
AU - de Vet, H.C.W.
AU - Terluin, B.
AU - Knol, D.L.
AU - Roorda, L.D.
AU - Mokkink, L.B.
AU - Ostelo, R.W.J.G.
AU - Hendriks, E.J.
AU - Terwee, C.B.
AU - Bouter, L.M.
PY - 2010
Y1 - 2010
N2 - Objective: Determining "minimally important change" (MIC) facilitates the interpretation of change scores on multi-item instruments. This article focuses on how MIC values should be interpreted when applied to individual patients. Study Design and Setting: The MIC value of a hypothetical questionnaire "Q" was determined in a sample of 400 patients who improved and 100 patients who did not improve, using the receiver operating characteristic (ROC) method, and three methods to quantify the uncertainty. Results: The MIC value on questionnaire Q was 10.5. Firstly, the 95% confidence interval (CI) of the MIC value (for questionnaire Q: 5.6-14.2) quantifies the uncertainty of the estimation of the MIC value. Secondly, "how sure we are that this MIC value holds for every patient" is quantified by the values for sensitivity (74%) and specificity (91%). Thirdly, the smallest detectable change (SDC) on questionnaire Q is calculated (16.0) to consider whether the MIC value (10.5) falls outside or within the measurement error. Conclusion: For application in clinical research and practice, MIC values are always considered at the individual level, but determined in groups of patients. The interpretation comes with different forms of uncertainty. To appreciate the uncertainty, knowledge of the underlying distributions of change scores is indispensable. © 2010 Elsevier Inc. All rights reserved.
AB - Objective: Determining "minimally important change" (MIC) facilitates the interpretation of change scores on multi-item instruments. This article focuses on how MIC values should be interpreted when applied to individual patients. Study Design and Setting: The MIC value of a hypothetical questionnaire "Q" was determined in a sample of 400 patients who improved and 100 patients who did not improve, using the receiver operating characteristic (ROC) method, and three methods to quantify the uncertainty. Results: The MIC value on questionnaire Q was 10.5. Firstly, the 95% confidence interval (CI) of the MIC value (for questionnaire Q: 5.6-14.2) quantifies the uncertainty of the estimation of the MIC value. Secondly, "how sure we are that this MIC value holds for every patient" is quantified by the values for sensitivity (74%) and specificity (91%). Thirdly, the smallest detectable change (SDC) on questionnaire Q is calculated (16.0) to consider whether the MIC value (10.5) falls outside or within the measurement error. Conclusion: For application in clinical research and practice, MIC values are always considered at the individual level, but determined in groups of patients. The interpretation comes with different forms of uncertainty. To appreciate the uncertainty, knowledge of the underlying distributions of change scores is indispensable. © 2010 Elsevier Inc. All rights reserved.
U2 - https://doi.org/10.1016/j.jclinepi.2009.03.011
DO - https://doi.org/10.1016/j.jclinepi.2009.03.011
M3 - Article
C2 - 19540720
SN - 0895-4356
VL - 63
SP - 37
EP - 45
JO - Journal of Clinical Epidemiology
JF - Journal of Clinical Epidemiology
IS - 1
ER -
