RESULTS We found that none of the 19 instruments have sufficiently comprehensive reporting of measurement or feasibility performance as would be required by regulatory authorities .
INTRODUCTION In an accompanying study we reported on the content of several activity rating scales that have been used for muscle disease .
To further aid in achieving consensus we conducted a systematic review to assess the quality of the 19 activity rating scales  design ed specifically for muscle disease .
Results and long-term followup of intravenous immunoglobulin infusions in chronic, refractory polymyositis: an open study with thirty-five adult patients.
OBJECTIVE Polymyositis is a rare inflammatory muscular disease of unknown cause . Corticosteroids and immunosuppressive drugs are the first choice of therapy but are not always effective and may cause serious side effects . Many studies have shown that polyvalent intravenous immunoglobulin ( IVIG ) may be of interest for the treatment of dermatomyositis . We carried out an open , prospect i ve study to evaluate the efficacy of IVIG in subjects with polymyositis that was refractory to traditional treatments , and we evaluated the benefits of this therapy over a long-term period of followup . METHODS Thirty-five adult white patients ( 20 female , 15 male , mean age 43.5 years [ SD 16.8 ] ) with chronic , refractory polymyositis were treated with high doses of IVIG , after the patients had received the following traditional treatments : prednisone ( n = 35 ) , methotrexate ( n = 24 ) , azathioprine ( n = 13 ) , cyclophosphamide ( n = 4 ) , cyclosporine ( n = 7 ) , chlorambucil ( n = 1 ) , plasmapheresis ( n = 8) , lymphopheresis ( n = 1 ) , and total body irradiation ( n = 1 ) . There had been no changes in the patients ' treatment in the 2 months before the initiation of IVIG therapy , and doses were not increased during IVIG treatment . We used preparations of polyvalent human IVIG with increased concentrations of intact IgG. The patients received 1 gm/kg/day for 2 consecutive days per month . The mean course of treatment was 4 - 6 months . The clinical assessment involved the evaluation of proximal muscle power , muscle disability scale score , and esophageal disorders . The biochemical evaluations carried out before each treatment period were compared by Student 's t-test and nonparametric Wilcoxon test . Results were considered to be significant at P = 0.05 . RESULTS In the short-term , significant clinical improvement was noted in 25 of the 35 patients ( 71.4 % ) . Mean muscle power was estimated before and after IVIG therapy and was found to be significantly improved ( P < 0.01 ) . All patients had a significant biochemical response . Mean creatine kinase levels during IVIG therapy decreased significantly before the fourth IVIG perfusion ( P < 0.01 ) . Side effects , usually minor , were noted in 6 patients . This benefit allowed the initial prednisone dose to be reduced by > 50 % in all patients . The mean ( + /- SD ) followup time for the 25 patients who responded favorably to IVIG treatment was 51.4 + /- 13.1 months . Twelve of these 25 patients remained in full remission following their initial course of IVIG , result ing in complete stoppage of medication in 5 patients or low doses of steroids in 7 patients . The condition of 6 patients remained improved and no other drugs were prescribed , but the patients remained dependent on IVIG infusions . Seven of the 25 patients who responded well to IVIG treatment relapsed at an average of 17.1 months ( range 4 - 23 months ) after the discontinuation of IVIG . CONCLUSION IVIG is an interesting therapy for the treatment of polymyositis , with results showing that the condition of approximately 70 % of the patients tested improved . After the discontinuation of the IVIG therapy , the efficacy remained stable in 50 % of the patients , with a followup of over 3 years
RESULTS We found that none of the 19 instruments have sufficiently comprehensive reporting of measurement or feasibility performance as would be required by regulatory authorities .
INTRODUCTION In an accompanying study we reported on the content of several activity rating scales that have been used for muscle disease .
To further aid in achieving consensus we conducted a systematic review to assess the quality of the 19 activity rating scales  design ed specifically for muscle disease .