muscle training therefore was negative, at -10 meters (or a 10 meter difference in favour of the control group). Here too, you should look for the 95% confidence intervals around this difference in changes in exercise capacity and consider their implications. The investigators tell us that the lower boundary of the 95% confidence interval was - 26 (that is, the results are consistent with a difference of 26 meters in favour of the control treatment) and the upper boundary was +5 meters. Even in the best of circumstances, adding 5 meters to the 400 recorded at the start of the trial would not be important to the patient, and this result effectively excludes a clinically significant benefit of respiratory muscle training as applied in this study. Having determined the magnitude and precision of the treatment effect, readers now can turn to the final question of how to apply the article's results to their patients and clinical practice. Will the results help me in caring for my patients? 1. Can the results be applied to my patient care? The first issue to address is how confident you are that you can apply the results to a particular patient or patients in your practice. If the patient would have been enroled in the study had she been there -- that is, she meets all the inclusion criteria, and doesn't violate any of the exclusion criteria -- there is little question that the results are applicable. If this is not the case, and