Thus the distribution method can only be used to calculate an absolute MCID as there is no st and ard deviation of baseline score for a relative measure .
The anchor-based method relates the change in
To the Editor : The same patient outcome data from clinical trial results , when presented as absolute or relative changes , may appear different in magnitude .
Recommendations are to report both absolute and relative , or at least baseline , data from which to calculate absolute values [ 1 , 2 ] .
To inform clinical practice , outcome improvements , whether relative or absolute , must be statistically significant and clinical ly meaningful .
A minimal clinical ly important difference ( MCID ) should inform sample size calculations for clinical trials .
Stable COPD: predicting benefit from high-dose inhaled corticosteroid treatment
The role of inhaled corticosteroids in the management of chronic obstructive pulmonary disease ( COPD ) remains controversial . The purpose of this study was to evaluate whether sputum eosinophilia ( defined as eosinophils ≥3 % ) predicts clinical benefit from inhaled corticosteroid treatment in patients with smoking-related clinical ly stable moderate-to-severe COPD . Forty consecutive patients with effort dyspnoea ( mean age 67 yrs ; 52 pack-yr smoking history ; post-bronchodilator forced expiratory volume in one second ( FEV1 ) < 60 % predicted , consistent with moderate-to-severe smoking-related chronic airflow limitation ) were enrolled . Subjects were treated with inhaled placebo followed by inhaled budesonide ( Pulmicort Turbuhaler ® 1,600 µg·day−1 ) , each given for 4 weeks . While the treatment was single-blind ( subject level ) , sputum cell counts before and after treatment interventions were double-blind , thus removing bias . Outcome variables included spirometry , quality -of-life assessment and 6-min walk test . Sputum eosinophilia was present in 38 % of subjects . In these , budesonide treatment normalised the eosinophil counts and , in comparison to placebo treatment , result ed in clinical ly significant improvement in the dyspnoea domain of the disease-specific chronic respiratory question naire ( 0.8 versus 0.3 ) and a small but statistically significant improvement in post-bronchodilator spirometry ( FEV1 100 mL versus 0 mL ; p<0.05 ) . In conclusion , sputum eosinophilia predicts short-term clinical benefit from high-dose inhaled corticosteroid treatment in patients with stable moderate-to-severe chronic obstructive pulmonary disease
Thus the distribution method can only be used to calculate an absolute MCID as there is no st and ard deviation of baseline score for a relative measure .
The anchor-based method relates the change in
To the Editor : The same patient outcome data from clinical trial results , when presented as absolute or relative changes , may appear different in magnitude .
Recommendations are to report both absolute and relative , or at least baseline , data from which to calculate absolute values [ 1 , 2 ] .
To inform clinical practice , outcome improvements , whether relative or absolute , must be statistically significant and clinical ly meaningful .
A minimal clinical ly important difference ( MCID ) should inform sample size calculations for clinical trials .