Objective evaluation of physical function in patients with advanced lung cancer: a preliminary report

This prospective study was designed in order to compare the most common subjective measurements of physical function in patients with advanced lung cancer with an objective physical functional test (Simmonds Functional Assessment Tool [SFA]).

One hundred patients agreed to participate and complete the study before or after their outpatient medical oncology appointment. Patients underwent assessment using the Karnofsky, the Brief fatigue Inventory, The Functional Assessment of Cancer Therapy-Lung patients (FACT-L) and the Edmonton Symptom Assessment Scale (ESAS). These results were compared to the SFA tool. The SFA consists of six tasks: tying a belt, putting coins in a cup, reaching above head, standing up/sitting down, reaching forward and walking 50 feet.

Ninety-nine patients completed the study over 8 months: median Karnofsky performance status was 85 (70 to 100), Edmonton Symptom Assessment Scale (ESAS) score (0 to 10) was generally low (0.5 to 2.8). SFA scores were significantly different in patients compared to a control group. The correlation between the subscales of the SFA and the Karnofsky, the Brief Fatigue Inventory, The FACT-L and the ESAS was generally low to moderate (r values: 0.22 to 0.38). There was generally a moderate correlation between the different subjective scales (r values: 0.3 to 0.62).

Adherence to the SFA tool was excellent. The low to moderate correlation between the abnormalities found in the objective SFA and the subjective fatigue tests suggest that objective evaluation of the functional capacity provides a potentially useful and independent end-point for clinical trials and therapeutic interventions. These assessment tools should be used complementary to each other to better assess the functional status of patients with advanced lung cancer. Large trials of objective functional assessment are justified.