The Medical Research Council grading system has served through decades for the evaluation of muscle strength and has been recognized as a cardinal feature of daily neurological, rehabilitation and general medicine examination of patients, despite being respectfully criticized due to the unequal width of its response options. No study has systematically examined, through modern psychometric approach, whether physicians are able to properly use the Medical Research Council grades. The objectives of this study were: (i) to investigate physicians’ ability to discriminate among the Medical Research Council categories in patients with different neuromuscular disorders and with various degrees of weakness through thresholds examination using Rasch analysis as a modern psychometric method; (ii) to examine possible factors influencing physicians’ ability to apply the Medical Research Council categories through differential item function analyses; and (iii) to examine whether the widely used Medical Research Council 12 muscles sum score in patients with Guillain–Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy would meet Rasch model's expectations. A total of 1065 patients were included from nine cohorts with the following diseases: Guillain–Barré syndrome (n = 480); myotonic dystrophy type-1 (n = 169); chronic inflammatory demyelinating polyradiculoneuropathy (n = 139); limb-girdle muscular dystrophy (n = 105); multifocal motor neuropathy (n = 102); Pompe's disease (n = 62) and monoclonal gammopathy of undetermined related polyneuropathy (n = 8). Medical Research Council data of 72 muscles were collected. Rasch analyses were performed on Medical Research Council data for each cohort separately and after pooling data at the muscle level to increase category frequencies, and on the Medical Research Council sum score in patients with Guillain–Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy. Disordered thresholds were demonstrated in 74–79% of the muscles examined, indicating physicians’ inability to discriminate between most Medical Research Council categories. Factors such as physicians’ experience or illness type did not influence these findings. Thresholds were restored after rescoring the Medical Research Council grades from six to four options (0, paralysis; 1, severe weakness; 2, slight weakness; 3, normal strength). The Medical Research Council sum score acceptably fulfilled Rasch model expectations after rescoring the response options and creating subsets to resolve local dependency and item bias on diagnosis. In conclusion, a modified, Rasch-built four response category Medical Research Council grading system is proposed, resolving clinicians’ inability to differentiate among its original response categories and improving clinical applicability. A modified Medical Research Council sum score at the interval level is presented and is recommended for future studies in Guillain–Barré syndrome and chronic inflammatory demyelinating polyradiculoneuropathy.

Objectives: Assessment of the long-term effect of uvulopalatopharyngoplasty (UPPP) on snoring, excessive daytime sleepiness, and nocturnal oxygen desaturation index (ODI) in patients with obstructive sleep apnea syndrome. Study Design: Evaluation of snoring, excessive daytime sleepiness, and ODI in patients treated by UPPP earlier. Materials and Methods: Patients (n ‫؍‬ 58) with a follow-up period of 11 to 74 months (median, 34 mo) were included in this study. Snoring and excessive daytime sleepiness were scored on specially designed semiquantitative scales. In all patients ODI was calculated from pulseoximetry combined with polysomnography at base line and by polygraphy (MESAM 4) during follow-up in 38 patients. Long-term response was compared with 6-month response in the same cohort. Results: There was a long-term improvement of snoring in 63% of patients, no change in 23%, and a deterioration in 14% (P < .00001). Overall snoring increased slightly between 6 months and long-term follow-up. There was an improvement of excessive daytime sleepiness in 38%, no change in 27%, and a deterioration in 35% (P ‫؍‬ .80). Excessive daytime sleepiness showed a relapse to preoperative levels between 6 months and long-term follow-up. The median improvement of ODI was ؊1 (95% interpercentile range, 73-51) and was not significant (P ‫؍‬ .35). In 5 of 13 patients in whom ODI at baseline exceeded 20, ODI was reduced to less than 20. In 4 of the 38 patients ODI was reduced to less than 5. The improvement of ODI decreased significantly between 6 months and long-term follow-up (P ‫؍‬ .03). No relation was found between body mass index, Mueller maneuver, X-cephalometry, and long-term outcome. An additional finding was that the ODI decreased after UPPP in combination with tonsillectomy, compared with a slight increase after UPPP alone; the difference was significant (P ‫؍‬ .008). Conclusion: The response to UPPP for obstructive sleep apnea syndrome decreases progressively over the years after surgery. UPPP in combination with tonsillectomy was more effective than UPPP alone.

Sixty consecutive patients with the obstructive sleep apnoea syndrome (53 men and seven women) were analysed by questionnaire, polysomnography, röntgenographic cephalometry and the Mueller manoeuvre before and 6 months after uvulopalatopharyngoplasty (UPPP), to assess the surgical outcome and the prognostic value of preoperative evaluation. Seventy-three per cent of patients reported improvement of snoring and 55% reported improvement of excessive daytime sleepiness. Thirty-five per cent showed a decrease of at least 50% in the desaturation index, and 13% had a postoperative desaturation index below 5. Although the improvement of desaturation parameters was marked in some patients, the overall change was not significant. Neither the Body Mass Index (BMI), nor any of the cephalometric variables were significantly correlated to surgical outcome. Increased difference in collapsibility between the soft palate and the base of the tongue showed a close to significant relation with the improvement of desaturation index. High desaturation index, low mean saturation and deep lowest saturation were found to be slightly predictive of improvement in nocturnal desaturation. In a multivariate analysis however no significant predictors could be identified. It is concluded that UPPP is effective in reducing snoring and daytime sleepiness over a 6-month follow-up period, but that the overall improvement in nocturnal desaturation is limited and difficult to predict. Further research is needed to evaluate the long-term efficacy of UPPP.

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Sixty patients, 53 men and 7 women, referred for excessive snoring or suspected sleep apnea syndrome were analyzed by polysomnography, Mueller maneuver, cephalometric roentgenography, and pulmonary function testing, to evaluate the contribution of static and dynamic upper airway obstruction in the pathogenesis of sleep-related breathing disorders and OSAS. Desaturation index and maximal desaturation were used in the analysis as indicators of severity of sleep-related breathing disorders. Body Mass Index, increased collapsibility at the base of the tongue by the Mueller maneuver, increased distance between hyoid and mandibular plane, and increased soft palate diameters by cephalometry as well as a decreased peak inspiratory flow by pulmonary function testing were found to be related to increased oxygen desaturation parameters. In a multivariate analysis the significant obstruction parameters could explain only 37% of the variability of maximum desaturation and 31% of the variability of desaturation index, 63 and 69%, respectively, must therefore be explained by other mechanisms. We conclude that instability of respiratory and muscular control, possibly enhanced by sleep-phase-related changes, is more important in the pathogenesis of sleep-related breathing disorders than pure anatomic narrowing of the airway.