Minimal clinically important difference of MFSI-SF for Asian breast cancer patients
The minimal clinically important difference (MCID) of the Multidimensional Fatigue Symptom Inventory-Short Form (MFSI-SF) for Asian breast cancer patients ranges from 4.50 to 10.79 points, a recent study from Singapore reveals.
“Our findings suggest that an increase between 4.50 and 10.79 points on the MFSI-SF is considered to be the smallest meaningful change that should motivate clinicians to mitigate cancer-related fatigue (CRF) in patients,” the researchers said.
“This finding was within our expectations because cancer and chemotherapy are known to cause considerable fatigue in cancer patients,” they added.
The research team conducted two surveys of 201 adult breast cancer patients (mean age 52.8±9.1 years) recruited from the National Cancer Centre in Singapore. Only those planning or already receiving chemotherapy were included.
The surveys were performed before any chemotherapy treatment cycle and at least 3 weeks later. Baseline demographic information were collected during the first survey, while MFSI-SF and quality of life were assessed in both surveys.
The mean total MFSI-SF scores increased from 0±19.53 in the first time point to 3.79±19.25 in the second; the difference reached statistical significance (3.80±15.16; p<0.001). [J Pain Symptom Manage 2017;S0885-3924(17)30594-8]
Quality of life, as measured by the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30, also significantly improved from the first to the second time point (26.26±21.35 vs 33.55±23.28; p<0.001).
Anchor-based estimates of the MCID revealed that a minimal increase of 8.69 (95 percent CI, 4.03 to 13.34; p<0.001) points was associated with significant deterioration in fatigue, whereas a decrease of 0.10 (-6.29 to 6.08; p=0.97), while associated with fatigue improvement, was not statistically significant.
“The MCID estimate for deterioration is of utmost importance in a clinical setting for interpreting changes in patients’ MFSI-SF scores. If the increase in fatigue is clinically significant, as represented by a change in score higher than the MCID, adjunctive interventions can be prescribed for patients to lessen fatigue while they are receiving chemotherapy,” the researchers explained.
The final estimates, obtained by combining values from the Youden index and the distribution-based method, revealed that the MCID ranged from 4.50 to 10.79 points.
Notably, the researchers found that baseline variables were influential in the determination of the MCID scores, with patients who had higher pain and fatigue at baseline requiring greater scores to report significant changes than those with lower baseline values.
“Pain is associated with fatigue, and therefore it was not surprising that patients who are in greater pain experience more fatigue. These results also supported the conclusions of another study about the baseline dependency of MCID,” they said. [J Pain Symptom Manage 2003;26:604-14; Phys Ther 2011;91:675-88]
“Hence, clinicians should be more cautious when using the MCID reported for groups of patients with higher baseline values.”