TY - JOUR
T1 - The assessment of fatigue: Psychometric qualities and norms for the Checklist individual strength
AU - Worm-Smeitink, M.
AU - Gielissen, M.
AU - Bloot, L.
AU - van Laarhoven, H. W. M.
AU - van Engelen, B. G. M.
AU - van Riel, P.
AU - Bleijenberg, G.
AU - Nikolaus, S.
AU - Knoop, H.
PY - 2017
Y1 - 2017
N2 - Objective: The Checklist Individual Strength (CIS) measures four dimensions of fatigue: Fatigue severity, concentration problems, reduced motivation and activity. On the fatigue severity subscale, a cut-off score of 35 is used. This study 1) investigated the psychometric qualities of the CIS; 2) validated the cut-off score for severe fatigue and 3) provided norms. Methods: Representatives of the Dutch general population (n = 2288) completed the CIS. The factor structure was investigated using an exploratory factor analysis. Internal consistency and test-retest reliability were determined. Concurrent validity was assessed in two additional samples by correlating the CIS with other fatigue scales (Choker Fatigue Questionnaire, MOS Short form-36 Vitality subscale, EORTC QLQ-C30 fatigue subscale). To validate the fatigue severity cut-off score, a Receiver Operating Characteristics analysis was performed with patients referred to a chronic fatigue treatment centre (n = 5243) and a healthy group (n = 1906). Norm scores for CIS subscales were calculated for the general population, patients with chronic fatigue syndrome (CFS; n = 1407) and eight groups with other medical conditions (n = 1411). Results: The original four-factor structure of the CIS was replicated. Internal consistency (a = 0.84-0.95) and test-retest reliability (r = 0.74-0.86) of the subscales were high. Correlations with other fatigue scales were moderate to high. The 35 points cut-off score for severe fatigue is appropriate, but, given the 17% false positive rate, should be adjusted to 40 for research in CFS. Conclusion: The CIS is a valid and reliable tool for the assessment of fatigue, with a validated cut-off score for severe fatigue that can be used in clinical practice
AB - Objective: The Checklist Individual Strength (CIS) measures four dimensions of fatigue: Fatigue severity, concentration problems, reduced motivation and activity. On the fatigue severity subscale, a cut-off score of 35 is used. This study 1) investigated the psychometric qualities of the CIS; 2) validated the cut-off score for severe fatigue and 3) provided norms. Methods: Representatives of the Dutch general population (n = 2288) completed the CIS. The factor structure was investigated using an exploratory factor analysis. Internal consistency and test-retest reliability were determined. Concurrent validity was assessed in two additional samples by correlating the CIS with other fatigue scales (Choker Fatigue Questionnaire, MOS Short form-36 Vitality subscale, EORTC QLQ-C30 fatigue subscale). To validate the fatigue severity cut-off score, a Receiver Operating Characteristics analysis was performed with patients referred to a chronic fatigue treatment centre (n = 5243) and a healthy group (n = 1906). Norm scores for CIS subscales were calculated for the general population, patients with chronic fatigue syndrome (CFS; n = 1407) and eight groups with other medical conditions (n = 1411). Results: The original four-factor structure of the CIS was replicated. Internal consistency (a = 0.84-0.95) and test-retest reliability (r = 0.74-0.86) of the subscales were high. Correlations with other fatigue scales were moderate to high. The 35 points cut-off score for severe fatigue is appropriate, but, given the 17% false positive rate, should be adjusted to 40 for research in CFS. Conclusion: The CIS is a valid and reliable tool for the assessment of fatigue, with a validated cut-off score for severe fatigue that can be used in clinical practice
U2 - https://doi.org/10.1016/j.jpsychores.2017.05.007
DO - https://doi.org/10.1016/j.jpsychores.2017.05.007
M3 - Article
C2 - 28554371
SN - 0022-3999
VL - 98
SP - 40
EP - 46
JO - Journal of psychosomatic research
JF - Journal of psychosomatic research
ER -