Concerning the feasibility of office spirometry, a first point to underline was that, notwithstanding most GPs participating in the study agreed on the usefulness of spirometry in their practice, only half of them accepted to use it regularly for the observational part of the study, and only a limited number agreed to take part in the comparative trial. The main reasons for not participating were lack of time, lack of confidence with research trials, and lack of compensation. Even the most cooperative GPs had an enrollment rate far lower than expected. As a consequence, the randomized trial was underpowered (as shown by the low-power figures in Table 2), introducing the risk of a type II statistical error. The rate of enrollment by each GP in the observational study was better than that in the randomized trial, probably because of less methodologic limitations.
The final judgement of GPs about the usefulness of office spirometry was not as enthusiastic as the one immediately after the run-in period, in agreement with our finding of a clear fading effect, in the long term, with regard to the use of office spirometry, as shown by the enrollment curve. If office spirometry really had been useful as stated in the questionnaires, we would have expected at least a steady intermediate-level application of the test and not a sharp progressive decrease to abolition in the last months of the study. http://asthma-inhalers-online.com/
This means that on a large scale, the application of office spirometry without periodic reinforcing sessions is subject to limitations in quantitative terms, aside from the problem of quality control and assurance that in our case relied solely on the automated built-in control of the spirometer. A close interaction with and strict technical support by specialist centers would be the optimal way to provide quality spirometry in general practice at present, although the epidemiologic challenge of asthma and COPD is already pushing toward a widespread development of pulmonary function testing in the nonspecialist setting. In 44 patients with complete evaluation, the GPs did not reach a definite diagnosis, leaving the task to the specialist. In all patients with a diagnosis from both the GP and pulmonary specialist, the agreement between GP and the specialist ranged from 49 to 83% of cases according to the different subanalyses, with no significant differences found between the two intervention subgroups.