Measuring agreement in method comparison studies

Bland, John M.; Altman, Douglas G.

doi:10.1177/096228029900800204

Cited by 6,530 publications

(4,716 citation statements)

References 16 publications

Supporting

Mentioning

4,611

Contrasting

Unclassified

Order By: Relevance

“…Intraobserver and interobserver reproducibility was performed using the intraclass correlation coefficient. 12,13 Stepwise, backwards, logistic regression was utilized to validate the influence of the two principle variables (Bishop score and vaginal sonographic cervical length) in the success of the induction and to validate the variables that predict any vaginal delivery. The influence of other variables as parity, BPD, maternal age, estimated fetal weight and previous miscarriages were also analyzed.…”

Section: Resultsmentioning

confidence: 99%

The labor induction: integrated clinical and sonographic variables that predict the outcome

et al. 2006

View full text Add to dashboard Cite

Objective: To analyze the clinical and sonographic variables that predicts the success of labor induction. Study design:We studied the Bishop score, cervical length and parity in 196 pregnant women in the prediction of successful vaginal delivery within 24 h of induction. Logistic regression and segmentation analysis were performed.Results: Cervical length (odds ratio (OR) 1.089, P<0.001), Bishop score (OR 0.751, P ¼ 0.001) and parity (OR 4.7, P<0.001) predict the success of labor induction. In a global analysis of the variables studied, the best statistic sequence that predicts the labor induction was found when we introduced parity in the first place. The success of labor induction in nulliparous was 50.8 and 83.3% in multiparous women (P ¼ 0.0001).Conclusions: Cervical length, Bishop score and parity, integrated in a flow chart, provide independent prediction of vaginal delivery within 24 h of induction.

show abstract

Section: Resultsmentioning

confidence: 99%

The labor induction: integrated clinical and sonographic variables that predict the outcome

et al. 2006

View full text Add to dashboard Cite

show abstract

“…Bland and Altman 6,7 also stress the importance of repeatability in assessing agreement between methods, as a method with poor repeatability will never agree well with another method. 6,7 The ideal model for assessment of agreement as described would have involved the same observer taking the different measurements to avoid interobserver variability; 6,7 however, because of the skill and experience required by each of the three methods, the measurements in this study were performed by different individuals. Interobserver variability was also introduced by having different surgeons (total four) estimating the hole size at time of operation; however, we consider that this represents the 'real-life' situation encountered by vitreoretinal surgeons.…”

Section: Discussionmentioning

confidence: 99%

“…6,7 To assess repeatability, we performed repeat measurements of macular hole size by masked analysis of a second digital photograph and a second OCT for each patient. Repeat surgeon estimate was not performed as the surgeon could not be adequately masked to their previous estimate during surgery.…”

Section: Methodsmentioning

confidence: 99%

Comparison of macular hole size measured by optical coherence tomography, digital photography, and clinical examination

Benson

Schlottmann

Bunce

et al. 2007

Eye

View full text Add to dashboard Cite

Aim To report on the agreement of macular hole size as measured using optical coherence tomography (OCT), Topcon digital photography, and surgeon estimate on clinical examination. Methods Observational cohort series of patients who underwent macular hole surgery over an 18-month period. Patients had OCT scan and digital fundus photographs preoperatively. At operation the surgeon estimated the size of macular hole. The agreement between methods was assessed using the technique described by Bland and Altman.Results There was good repeatability of photographic and OCT assessment and no evidence of systematic bias between repeated macular hole measurement by digital photography (P ¼ 0.36) or by OCT (P ¼ 0.58). There was evidence of systematic bias between photographic and surgeon measurements (Po0.001), and between OCT and surgeon (Po0.001) with photographic and OCT assessment being greater. There was also evidence of bias between OCT and photographic measurements with photographic measurement tending to be greater than the OCT measurement for smaller holes and lower for larger holes (P ¼ 0.02). Conclusions OCT and Topcon digital photography have good repeatability for measurement of macular hole size. Both these methods measured larger hole sizes compared to surgeon estimate. Digital photography and OCT methods did not agree.

show abstract

“…The performance of each algorithm was assessed by determining how well the timings of the kinematically derived TD and FO events 'agreed' with those derived using the GRF, using 'limits of agreement' (LoA) analyses [16]. A LoA analysis assesses the agreement between two different methods that measure the same quantity, and is often used to assess how much a new measurement method is likely to differ from the old (existing and/or 'gold standard' method) [16].…”

Section: The Algorithmsmentioning

confidence: 99%

“…A LoA analysis assesses the agreement between two different methods that measure the same quantity, and is often used to assess how much a new measurement method is likely to differ from the old (existing and/or 'gold standard' method) [16]. Such analysis determines the mean difference between the two measurement methods (bias), along with 95% agreement limits which determine the precision (range of agreement).…”

Section: The Algorithmsmentioning

confidence: 99%

Stair-specific algorithms for identification of touch-down and foot-off when descending or ascending a non-instrumented staircase

et al. 2014

View full text Add to dashboard Cite

Research HighlightsAlgorithms defining touch-down and foot-off (TD/FO) in stair ambulation are presented Performance of these algorithms was determined by comparison to force defined events TD/ FO were determined with acceptable precision in young and old adultsThe algorithms performed equally well at differing riser heights (85-255 mm)These algorithms can be used when force-instrumented staircases are unavailable AbstractThe present study introduces four event detection algorithms for defining touch-down and foot-off during stair descent and stair ascent using segmental kinematics. For stair descent, vertical velocity minima of the whole body centre-of-mass was used to define touch-down, and foot-off was defined as the instant of trail limb peak knee flexion. For stair ascent, vertical velocity local minima of the lead-limb toe was used to define touch-down, and footoff was defined as the local maxima in vertical displacement between the toe and pelvis. The performance of these algorithms was determined as the agreement in timings of kinematically derived events to those defined kinetically (ground reaction forces). Data were recorded while 17 young and 15 older adults completed stair descent and ascent trials over a four-step instrumented staircase. Trials were repeated for three stair riser height conditions (85 mm, 170 mm, and 255 mm). Kinematically derived touch-down and foot-off events showed good agreement (small 95% limits of agreement) with kinetically derived events for both young and older adults, across all riser heights, and for both ascent and descent. In addition, agreement metrics were better than those returned using existing kinematically derived event detection algorithms developed for overground gait. These results indicate that touch-down and foot-off during stair ascent and descent of non-instrumented staircases can be determined with acceptable precision using segmental kinematic data.

show abstract

Measuring agreement in method comparison studies

Cited by 6,530 publications

References 16 publications

The labor induction: integrated clinical and sonographic variables that predict the outcome

The labor induction: integrated clinical and sonographic variables that predict the outcome

Comparison of macular hole size measured by optical coherence tomography, digital photography, and clinical examination

Stair-specific algorithms for identification of touch-down and foot-off when descending or ascending a non-instrumented staircase

Contact Info

Product

Resources

About