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BACKGROUND CONTEXT

Health-related quality of life (HRQOL) parameters have been shown to be reliable and valid in patients with adult spinal deformity (ASD). Minimum clinically important difference (MCID) has become increasingly important to clinicians in evaluating patients with a threshold of improvement that is clinically relevant.

PURPOSE

To calculate MCID and minimum detectable change (MDC) values of total scores of the Core Outcome Measures Index (COMI), Oswestry Disability Index (ODI), Physical Component Summary (PCS), Mental Component Summary (MCS) of the Short Form 36 (SF-36), and Scoliosis Research Society 22R (SRS-22R) in surgically and nonsurgically treated ASD patients who have completed an anchor question at pretreatment and 1-year follow-up.

STUDY DESIGN/SETTING

Prospective cohort.

PATIENT SAMPLE

Surgical and nonsurgical patients from a multicenter ASD database.

OUTCOME MEASURES

Self-reported HRQOL measures (COMI, ODI, SF-36, SRS-22R, and anchor question).

METHODS

A total of 185 surgical and 86 nonsurgical patients from a multicenter ASD database who completed pretreatment and 1-year follow-up HRQOL scales and the anchor question at the first year follow-up were included. The anchor question was used to determine MCID for each HRQOL measure. MCIDs were calculated by an anchor-based method using latent class analysis (LCA) and MDCs by a distribution-based method.

RESULTS

All differences between means of baseline and first year postoperative total score measures for all scales demonstrated statistically significant improvements in the overall population as well as the surgically treated patients but not in the nonsurgical group. The calculated MDC and MCID values of HRQOL parameters in the entire study population were 1.34 and 2.62 for COMI, 10.65 and 14.31 for ODI, 6.09 and 7.33 for SF-36 PCS, 6.14 and 4.37 for SF-36 MCS, and 0.42 and 0.71 for SRS-22R. The calculated MCID values for surgical and non-surgical treatment groups were 2.76 versus 1.20 for COMI, 14.96 versus 2.45 for ODI, 7.83 versus 2.15 for SF-36 PCS, 5.14 versus 2.03 for SF-36 MCS, and 0.94 versus 0.11 for SRS-22R; the MDC values for surgical and nonsurgical treatment groups were 1.22 versus 1.51 for COMI, 10.27 versus 9.45 for ODI, 5.16 versus 6.77 for SF-36 PCS, 6.05 versus 5.67 for SF-36 MCS, and 0.38 versus 0.43 for SRS-22R.

CONCLUSIONS

This study has demonstrated that MCID calculations for the HRQOL scales in ASD using LCA yield values comparable to other studies that had used different methodologies. The most important finding was the significantly different MCIDs for COMI, ODI, SF-36 PCS and SRS-22 in the surgically and nonsurgically treated cohorts. This finding suggests that a universal MCID value, inherent to a specific HRQOL for an entire cohort of ASD may not exist. Use of different MCIDs for surgical and nonsurgical patients may be warranted.  相似文献   
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Non-A, non-B is a major form of hepatitis in haemodialysis (HD)patients. Hepatitis C virus (HCV) has been recently identifiedas the leading cause of non-A, non-B hepatitis in HD. A variableprevalence of hepatitis in HD has appeared in the literature,ranging between 1% and 29% in the Western world, and between30% and 54% in Saudi Arabia, but all these reports used first-generationELISA. Using second-generation enzyme immunoassay, we conducteda multi-centre study involving 22 HD centres all over SaudiArabia in order to establish the prevalence and risk factorsfor HCV in HD patients in Saudi Arabia. A total of 1147 patientswere studied, with a mean age of 43.4±15.3 years. Fivehundred and eighty were males and 567 were females. The overallprevalence rate of positive anti-HCV was 68%, with a range fromas low as 14.5%, to 94.7%. To our knowledge, this is the highestvalue reported among dialysis patients world-wide. A positivecorrelation was found between anti-HCV positivity and male sex(P=0.005), longer duration on dialysis (P=0.002) and blood transfusion(P=0.003). However, interestingly 62.6% of the patients whohad not had blood transfusion had anti-HCV antibodies. HCV antibodieswere also found more frequently in Egyptians, Pakistanis andYemenis than in Saudis. A comparison between those centres withlow prevalence of positive HCV and those with high prevalenceregarding risk factors was carried out, and it was found thatthe major difference between them was the adherence of the staffto universal infection precautions. In conclusion, HCV is amajor health problem in HD patients in Saudi Arabia. Identifiablerisk factors are longer duration in dialysis, blood transfusion,male sex, nationality and most importantly the lack of adherenceto universal infection precautions.  相似文献   
5.
The aim of the study was to determine if prematurely born children who had suffered intra-uterine growth retardation (IUGR) had more severe lung function abnormalities than those born an appropriate weight for gestational age (AGA). Analysis of the lung function results of 119 infants (median (range) gestational age of 30 (23-35) weeks) was undertaken. In total, 31 of the infants had suffered IUGR and were born small for gestational age (SGA). Functional residual capacity and airways resistance (Raw) were measured at a median post-natal age of 10 (6-24) months. Specific airway conductance (sGaw) was calculated from thoracic gas volume and Raw. The SGA children were born at a greater gestational age and had a lower body weight at testing than the AGA children. Raw and sGaw differed between the SGA and AGA children. Regression analysis demonstrated that lung volumes were significantly related to body weight at testing, Raw was related to IUGR, maternal smoking and bronchopulmonary dysplasia, and sGaw to maternal smoking. In conclusion, these results suggest that prematurely born infants who have suffered intra-uterine growth retardation may be at increased risk of impaired lung function at follow-up.  相似文献   
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Physiological analysis to quantify training load in badminton.   总被引:2,自引:1,他引:1       下载免费PDF全文
OBJECTIVE: To estimate the training load of specific on court training regimens based on the magnitude of variation of heart rate-lactate response during specific training and to determine the magnitude of variation of biochemical parameters (urea, uric acid, and creatine phosphokinase (CPK)) 12 hours after the specific training programme so as to assess training stress. METHODS: The study was conducted on six national male badminton players. Maximum oxygen consumption (VO2), ventilation (VE), heart rate, and respiratory quotient were measured by a protocol of graded treadmill exercise. Twelve training sessions and 35 singles matches were analysed. Heart rate and blood lactate were monitored during technical training routines and match play. Fasting blood samples collected on two occasions--that is, during off season and 12 hours after specific training--were analysed for serum urea, uric acid, and CPK. RESULTS: Analysis of the on court training regimens showed lactate values of 8-10.5 mmol/l in different phases. The percentage of maximum heart rate ranged from 82% to 100%. Urea, uric acid, and CPK activity showed significant changes from (mean (SD)) 4.93 (0.75) mmol/l to 5.49 (0.84) mmol/l, 0.23 (0.04) to 0.33 (0.06) mmol/l, and 312 (211.8) to 363 (216.4) IU/l respectively. CONCLUSION: Maximum lactate reported in the literature ranges from 3-6 mmol/l. Comparatively high lactate values and high percentage of maximum heart rate found in on court training show a considerable stress on muscular and cardiovascular system. The training load needs appropriate monitoring to avoid over-training. Workouts that are too intensive may interfere with coordination, a factor that is important in sports requiring highly technical skill such as badminton.  相似文献   
8.
Purpose: to determine wheather an association exists between sensorineural hearing loss and pseudoexfoliation. Methods: Hearing thresholds were determined by using pure-tone au-diometry in 75 patients with pseudoexfoliation syndrome and in the control group of 75 subjects without pseudoexfoliation The groups were sex and age matched. Results: The frequency of  相似文献   
9.
Purpose: To report clinically, anotomically and angiographically documented cystoid macular edema (CME) associated with the use of latanoprost in 2 uncomplicated pseudophakic eyes. Methods: Retrospective rewiev of 2 patients who had history of latanoprost use and uncomplicated cataract surgery, described  相似文献   
10.
Abstract: In order to determine the pulmonary toxicity of kerosene and its ignition product (soot) in asbestos exposed subjects, the activities of phase I and phase II drug metabolizing enzymes in rat lungs after single intratracheal coexposure to Indian chrysotile asbestos and kerosene or its soot and Indian chrysotile were assayed. Exposure to kerosene or its soot resulted in a significant increase in the level of microsomal cytochrome P-450 and the activity of P-450 dependent monooxygenase, benzo(a)pyrene hydroxylase, as well as in the activities of microsomal epoxide hydrase and cytosolic glutathione-S-transferase (GST). However, in chrysotile exposed animals a reverse pattern in these parameters was recorded. The co-exposure to chrysotile and kerosene or chrysotile and soot led to a significant depletion in cytochrome P-450 level and a decrease in the activities of benzo(a)pyrene hydroxylase, epoxide hydrase and GST when compared to kerosene and soot controls, respectively. These results suggest that asbestos by altering the pulmonary drug metabolizing enzyme system may increase the toxic potential of kerosene and its ignition product in the respiratory system.  相似文献   
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