ISSN:0894-9115    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0894-9115    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0894-9115    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Recording the tibial H reflex from the calf is routine in clinical electromyography. Two widely used methods are Hugon's and Braddom and Johnson's. Both methods produce an H wave with an initial positive deflection. Another method, the "half and half" method, generates an H wave with an initial negative deflection. To compare these methods, H-reflex responses were recorded in the right calf of 20 normal adults with each method using identical amplifier and stimulator settings. Stimulus current was increased by increments of 0.5-1.0 mA until the H reflex and motor (M) wave responses reached maximum amplitudes (Hmax, Mmax). H wave to M wave (H/M) amplitude ratios were calculated. The half-and-half method produced greatest Hmax, Mmax, and H/M ratio. Wave form configuration for the half-and-half method was biphasic with an initial negative deflection; it was triphasic with an initial positive deflection with the other methods. The shapes of M and H waves were similar in two methods but dissimilar in one. Because of the greater amplitude and the initial negative deflection, the H wave may be easier to detect with the half-and-half method and may present a latency that is more easily determined. For these reasons, the half-and-half method is recommended for measuring amplitude and latency in clinical settings.

ISSN:0894-9115    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0894-9115    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

The purpose of this article is to provide researchers and clinicians with a basic understanding of randomized clinical trials and to discuss their potential application to and limitations in the field of physical medicine and rehabilitation. A brief history of the development of randomized clinical trials, definitions of clinical trials, types of trials, and overview of methodological issues related to design are offered. Information is provided about the need to establish clear and concise study objectives and to explicitly define interventions and expected outcomes. Recommendations for developing clinical protocols and determining adequate sample size are presented, and various statistical considerations, including power, are discussed. Issues related to sampling strategies, and recruitment are reviewed. Importance of randomization and blinding is emphasized. Readers are also referred to other resources available on this topic. Finally, the authors describe shortfalls associated with the use of this design in rehabilitation research. These are further explored and discussed in terms of the actual benefits and limitations of randomized clinical trials in physical medicine and rehabilitation research. Recommendations are made regarding the use of this methodology to address relevant needs in clinical practice.

ISSN:0894-9115    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0894-9115    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0894-9115    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0894-9115    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0894-9115    

出版商:OVID    

年代:1999

数据来源: OVID