Background: Progress in the treatment of breathlessness at rest or on minimum exertion in patients with cancer requires a practical and valid method of measuring symptoms. A study was undertaken to explore the practicality, repeatability, and sensitivity of reading numbers as a form of exercise test in this group of patients.
Methods: Thirty patients with cancer and 30 age matched healthy subjects read numbers aloud as quickly and clearly as they could for 60 seconds. After five readings the maximum number of numbers read and the number read per breath was noted. This procedure was carried out twice in one day and one week later to assess within and between day repeatability. The sensitivity of the test was assessed by making measurements in 13 patients with cancer before and after drainage of their pleural effusion.
Results: The concept was easily understood by all subjects. Twelve patients were unable to complete five readings in all tests due to tiredness. Compared with control subjects patients read fewer numbers in the three tests (87-89% of control) and fewer numbers per breath (59-60% of control). Repeatability was good both within and between days. After drainage of their effusion all patients were less breathless and there was an increase in both the maximum number of numbers read (23%) and the number read per breath (60%).
Conclusions: The number of numbers read and the number read per breath over 60 seconds was practical, easy to carry out, showed good repeatability within and between days and was sensitive to the improvement seen following drainage of a pleural effusion. It may be a useful measure of the limiting effect of breathlessness in this group of patients.