Intra-rater reliability

About: Intra-rater reliability is a research topic. Over the lifetime, 2073 publications have been published within this topic receiving 140968 citations.

An elementary guide to reliability

Abstract: Introduction The importance of reliability Definitions of reliability Some simple statistics How reliability is calculated The effect of operating conditions and environments Mechanical reliability Installation and operability Maintainability Reporting failures Design of fault tolerant systems The cost of reliability Some useful reliability definitions Further reading Index

A study examining inter-rater and intrarater reliability of a novel instrument for assessment of psoriasis: the Copenhagen Psoriasis Severity Index.

Abstract: BACKGROUND: There is a perceived need for a better method for clinical assessment of the severity of psoriasis vulgaris. The most frequently used system is the Psoriasis Area and Severity Index (PASI), which has significant disadvantages, including the requirement for assessment of the percentage of skin affected, an inability to separate milder cases, and a lack of linearity. The Copenhagen Psoriasis Severity Index (CoPSI) is a novel approach which comprises assessment of three signs: erythema, plaque thickness and scaling, each on a four-point scale (0, none; 1, mild; 2, moderate; 3, severe), at each of 10 sites: face, scalp, upper limbs (excluding hands and wrists), hands and wrists, chest and abdomen, back, buttocks and sacral area, genitalia, lower limbs (excluding feet and ankles), feet and ankles. OBJECTIVES: To evaluate the inter-rater and intrarater reliability of the CoPSI and to provide comparative data from the PASI and a Physician's Global Assessment (PGA) used in recent clinical trials on psoriasis vulgaris. METHODS: On the day before the study, 14 dermatologists (raters) with an interest in psoriasis participated in a detailed training session and discussion (2.5 h) on use of the scales. On the study day, each rater evaluated 16 adults with chronic plaque psoriasis in the morning and again in the afternoon. Raters were randomly assigned to assess subjects using the scales in a specific sequence, either PGA, CoPSI, PASI or PGA, PASI, CoPSI. Each rater used one sequence in the morning and the other in the afternoon. The primary endpoint was the inter-rater and intrarater reliability as determined by intraclass correlation coefficients (ICCs). RESULTS: All three scales demonstrated 'substantial' (a priori defined as ICC > 80%) intrarater reliability. The inter-rater reliability for each of the CoPSI and PASI was also 'substantial' and for the PGA was 'moderate' (ICC 61%). The CoPSI was better at distinguishing between milder cases. CONCLUSIONS: The CoPSI and the PASI both provided reproducible psoriasis severity assessments. In terms of both intrarater and inter-rater reliability values, the CoPSI and the PASI are superior to the PGA. The CoPSI may overcome several of the problems associated with the PASI. In particular, the CoPSI avoids the need to estimate a percentage of skin involved, is able to separate milder cases where the PASI lacks sensitivity, and is also more linear and simpler. The CoPSI also incorporates more meaningful weighting of different anatomical areas.

Intra-rater reliability and agreement of muscle strength, power and functional performance measures in patients with hip osteoarthritis.

Abstract: Objective: To investigate the reliability and agreement of measures of lower extremity muscle strength, power and functional performance in patients with hip osteoarthritis at different time intervals, and to compare these with the same measures in healthy peers. Design: Intra-rater test-retest separated by 1, 2, or 2.5 weeks in patients, and 1 week in healthy peers. Subjects: Patients with hip osteoarthritis (age range 61–83 years) with 1 (n = 37), 2 (n = 35), or 2.5 weeks (n = 15) between tests, and 35 healthy peers (age range 63–82 years). Methods: Maximal isometric hip and thigh strength, leg extensor power, and functional performance (8-foot up&go, stair climbing, chair stand and 6-min walk) were measured in patients, and quadriceps strength, leg extensor power and functional performance were measured in healthy peers. Systematic error, reliability and agreement were calculated. Results: Most hip strength measurements for the most symptomatic extremity, and nearly all strength measurements for the least symptomatic lower extremity, declined after 1 week (p < 0.05), but not after a 2.5-week interval. In healthy peers, quadriceps strength was unchanged. Regardless of the time interval, leg extensor power was unchanged, while functional performances improved at retest for all participants. Conclusion: In patients with hip osteoarthritis leg extensor power is unaffected by the time interval between tests, in contrast to muscle strength and functional performance.

Reliability of Shoulder Internal Rotation Passive Range of Motion Measurements in the Supine Versus Sidelying Position

Abstract: Study Design Clinical measurement, reliability. Objective To compare intrarater and interrater reliability of shoulder internal rotation (IR) passive range of motion measurements utilizing a standard supine position and a sidelying position. Background Glenohumeral IR range of motion deficits are often noted in patients with shoulder pathology. Excellent intrarater reliability has been found when measuring this motion. However, interrater reliability has been reported as poor to fair. Some clinicians currently use a sidelying position for IR stretching with patients who have shoulder pathology. However, no objective data exist for IR passive range of motion measured in this sidelying position, either in terms of reliability or normative values. Methods Seventy subjects (mean age, 36.8 years), with (n = 19) and without (n = 51) shoulder pathology, were included in this study. Shoulder IR passive range of motion of the dominant shoulder or involved shoulder was measured by 2 investigators in 2 positions: (1...