American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Feb 2014
ReviewMinimal Clinically Important Differences in Pharmacological Trials.
The concept of a minimal clinically important difference (MCID) is well established. Here, we review the evidence base and methods used to define MCIDs as well as their strengths and limitations. Most MCIDs in chronic obstructive pulmonary disease (COPD) are empirically derived estimates applying to populations of patients. ⋯ In a clinical trial setting, many factors, including study duration, withdrawal rate, baseline severity, and Hawthorne effects, can influence the measured treatment effect and determine whether it reaches the MCID. We also address recent challenges presented by clinical trials that compare active treatments and suggest that MCIDs should be used to identify the additional proportion of patients who benefit, for example, when one drug is replaced by another or when a second drug is added to a first. We propose the term "minimum worthwhile incremental advantage" to describe this parameter.
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Am. J. Respir. Crit. Care Med. · Feb 2014
The Site and Nature of Airway Obstruction after Lung Transplantation.
The chronic rejection of lung allografts is attributable to progressive small airway obstruction. ⋯ Chronic lung allograft rejection is associated with a progressive form of constrictive bronchiolitis that targets conducting airways while sparing larger airways as well as terminal bronchioles and the alveolar surface.