Smallest Detectable Difference Research Articles

SAT0499 Power Doppler Ulrasonographic Monitoring of Response to Treatment in Gout Patients

BackgroundThe accepted outcome measures for gout are seric urate, recurrent outbreaks, tophi regression and joint damage image. The Power Doppler ultrasound (PDUS) has demonstrated validity in the monitoring of treatment...

Test-retest reliability and sensitivity of the 20-meter walk test among patients with knee osteoarthritis

BackgroundThe 20-meter walk test is a physical function measure commonly used in clinical research studies and rehabilitation clinics to measure gait speed and monitor changes in patients’ physical function over time. Unfortunately, the reliability and sensitivity of this walk test are not well defined and, therefore, limit our ability to evaluate real changes in gait speed not attributable to normal variability. The aim of this study was to assess the test-restest reliability and sensitivity of the 20-meter walk test, at a self-selected pace, among patients with mild to moderate knee osteoarthritis (OA) and to suggest a standardized protocol for future test administration.MethodsThis was a measurement reliability study. Fifteen consecutive people enrolled in a randomized-controlled trial of intra-articular corticosteroid injections for knee OA participated in this study. All participants completed 4 trials on 2 separate days, 7 to 21 days apart (8 trials total). Each day was divided into 2 sessions, which each involved 2 walking trials. We compared walk times between trials with Wilcoxon signed-rank tests. Similar analyses compared average walk times between sessions. To confirm these analyses, we also calculated Spearman correlation coefficients to assess the relationship between sessions. Finally, smallest detectable differences (SDD) were calculated to estimate the sensitivity of the 20-meter walk test.ResultsWilcoxon signed-rank tests between trials within the same session demonstrated that trials in session 1 were significantly different and in the subsequent 3 sessions, the median differences between trials were not significantly different. Therefore, the first session of each day was considered a practice session, and the SDD between the second session of each day were calculated. SDD was −1.59 seconds (walking slower) and 0.15 seconds (walking faster).ConclusionsPractice trials and a standardized protocol should be used in administration of the 20-meter walk test. Changes in walk time between −1.59 seconds (walking slower) and 0.15 seconds (walking faster) should be considered within the range of normal variability of 20-meter walking speed. The primary limitation of our study was a small sample size, which may influence the generalizability of our findings.

Reliability and validity of the Trunk Impairment Scale in children and adolescents with cerebral palsy

Standardized clinical tools are useful for treatment planning and evaluation, however clinical tools to assess quality in trunk movements in children with cerebral palsy (CP) are sparse. We have recently reported good intra- and inter-observer reliability of the Trunk Impairment Scale (TIS) in 5-12 year old children with CP. The aim of this study was to assess reliability in adolescents (13-19 years old), and to assess the construct validity in children and adolescents in the whole age spectrum from 5 to 19 years. Video recordings of 17 children with CP with Gross Motor Function Classification (GMFCS) level I-IV were analyzed by three observers on two occasions. For construct validity the TIS was compared with Gross Motor Function Measure (GMFM), in 37 children with GMFCS levels I-IV. Intraclass correlation coefficients varied between 0.82 and 0.98, and 86% of the kappa values varied between 0.61 and 1.00, suggesting high inter- and intra-observer reliability. The smallest detectable difference (SDD) of the TIS (scale range 0-23) varied between 2.55 and 3.82 for intra- and 4.07-8.23 for inter-observer observations. The high inter-observer SDD was partly due to consistently lower TIS scores by one observer. The correlation between the TIS total score and the dimension scores of the GMFM was high (Spearman's rho: 0.80-0.87), while decreasing GMFCS levels were associated with increasing total TIS score; both findings indicating good construct validity of the TIS. This study suggests that the TIS is a reliable and valid measure of trunk control for both children and adolescents with cerebral palsy.

Repair of erosions in patients with rheumatoid arthritis treated with etanercept: magnetic resonance imaging findings after 1 year of follow-up

Objectives: To monitor repair of bone erosions using magnetic resonance imaging (MRI) in patients with rheumatoid arthritis (RA) during etanercept combination therapy.Method: The study population comprised 29 RA patients [biologic-naïve, 28-joint Disease Activity Score (DAS28) ≥ 3.2] starting etanercept combination therapy with disease-modifying anti-rheumatic drugs (DMARDs) and completing the 1-year study period with the same treatment. Clinical and laboratory assessments and MRI of the hand were performed at baseline and at 1 year. MRI findings were scored by two readers using the Rheumatoid Arthritis MRI Scoring System (RAMRIS). Both readers were blind to the chronological order of the MRI scans, the identity of the patients, and clinical and other imaging data. Tenosynovitis was also scored. The intra- and inter-reader intraclass correlation coefficients (ICCs) were calculated, along with the sensitivity to change with the smallest detectable difference (SDD). Repair of erosions was defined as a RAMRIS score of at least 1 point lower than baseline.Results: The mean RAMRIS score for erosions did not change but all other inflammatory MRI parameters decreased significantly. In 19 patients, the RAMRIS score for erosions remained unchanged after 1 year. In five patients the score decreased after 1 year, although the decrease exceeded the SDD in only one patient (3.4%).Conclusions: Etanercept combined with DMARDs stopped the progression of erosions, as measured by the RAMRIS, in 82.8% of our RA patients and occasional repair of bone erosions occurred after 1 year of treatment.

Assessment of the test–retest reliability of a foot placement accuracy protocol in assisted-living older adults

IntroductionThis study assessed the test–retest reliability of a foot placement accuracy protocol in a population of assisted-living elderly. The goal was to evaluate the execution of foot placement performance with increasing complexity of the walking condition. MethodsTwenty-five elderly participants (5 males, 20 females, 80.4±8.6 years) were assessed by one observer in two sessions with 48h between the measurements. Participants walked at self-selected pace along a pathway with three different walking conditions composed of two rectangular foam target locations and an obstacle on the walking surface. The main outcome measures were foot placement distance error, intra-class correlation coefficients (ICC), and the smallest detectable difference (SDD). ResultsMean absolute values of the foot placement distance errors were 14.0±4.5mm for medio-lateral deviation and 27.2±2.1mm for anterior–posterior deviation, respectively. ICC values for test–retest reliability showed ‘fair to good’ to ‘excellent’ reliability across all conditions with values ranging from 0.63 to 0.94. SDD values were between 3.6 and 37.3mm. ConclusionThe protocol showed good reliability for test–retest measurements of foot placement accuracy, thus making this protocol a reliable and location-independent tool to assess performance of foot placement in elderly in assisted-living settings. In the future, measurements with elderly fallers and non-fallers should be conducted to assess validity of the protocol.

Reproducibility and Validity of the 10-Meter Shuttle Ride Test in Wheelchair-Using Children and Adolescents With Cerebral Palsy

For children with cerebral palsy (CP) who are able to walk or run, the 10-m shuttle run test is currently the test of choice to assess cardiorespiratory fitness. This test, however, has not yet been examined in wheelchair-using youth with CP. The purpose of this study was to investigate the test-retest reproducibility and validity of the 10-m shuttle ride test (SRiT) in youth with CP. Repeated measurements of the SRiT were obtained. Twenty-three individuals with spastic CP (18 boys, 5 girls; mean age=13.3 years, SD=3.6 years) using a manual wheelchair for at least part of the day participated in this study. During the study, all participants performed one graded arm exercise test (GAET) and 2 identical SRiTs within 2 weeks. Peak oxygen uptake (Vo2peak), peak heart rate (HRpeak), and respiratory exchange ratio (RER) were recorded. Intraclass correlation coefficients (2,1), the smallest detectable difference, and the limits of agreement (LOA) were calculated. The association between the results of the SRiT and GAET was tested using Pearson correlation coefficients. Intraclass correlation coefficients (.99, 95% confidence interval=.98-1.00) for all variables indicated highly acceptable reproducibility. The LOA analysis revealed satisfactory levels of agreement. The SRiT variables demonstrated strong, significant positive correlations for Vo2peak values obtained during the SRiT and the GAET (r=.84, P<.01). Although the GAET is considered the gold standard, the cardiorespiratory demand during the GAET was significantly lower compared with during the SRiT. Future studies should determine whether the GAET can still be accepted as the gold standard for upper-extremity exercise. The SRiT is a reproducible and valid test for measuring cardiorespiratory fitness in youth with spastic CP who self-propel a manual wheelchair.

Reliability of Isometric Lower-Extremity Muscle Strength Measurements in Children With Cerebral Palsy: Implications for Measurement Design

Children with cerebral palsy (CP) typically show muscle weakness of the lower extremities, which can be measured with the use of handheld dynamometry (HHD). The purposes of this study were: (1) to determine test-retest reliability and measurement error of isometric lower-extremity strength measurements in children with CP with the use of HHD and (2) to assess implications for measurement design. A test-retest design was used. Fourteen children with hemiplegic (n=6) or diplegic (n=8) spastic CP (Gross Motor Function Classification System levels I-III), ages 7 to 13 years, were assessed for isometric strength on 2 separate days (occasions) with the use of HHD, with 3 trials per muscle group. The intraclass correlation coefficient, standard error of measurement, and smallest detectable difference (SDD) were calculated for different measurement designs. Intraclass correlation coefficient values of single measurements for all muscle groups ranged from .70 to .90, and the SDD was large (>30%). Regarding measurement error, the largest source of variability was found for occasion. A 2-occasion mean decreased the SDD by 9% to 14%. For trials, a greater improvement in SDD was found when 2 trials were averaged instead of 3. A measurement design of 2 trials-2 occasions was superior to the often-used approach of 3 trials-1 occasion. The small sample size was the major study limitation. Handheld dynamometry is reliable and can be used to detect changes in isometric muscle strength in children with CP when using the mean of at least 2 trials. To further improve reliability, taking the average of 2 occasions on separate days is recommended, depending on group size and muscle group.

Reliability and sensitivity of the 20-meter walk test among patients with knee osteoarthritis

Purpose: The 20-meter walk test is a physical function measure commonly used in clinical research studies and rehabilitation clinics to measure gait speed and monitor changes in patients’ physical function over time. Unfortunately, the reliability and sensitivity of this walk test are not well defined and therefore limit our ability to evaluate changes in gait speed. The aim of this study was to assess the reliability and sensitivity of the 20-meter walk test, at a self-selected pace, among patients with knee osteoarthritis (OA). Methods: This was a measurement reliability study that included fifteen consecutive participants enrolled in a randomized-controlled trial of intra-articular corticosteroid injections for knee OA. The study sample included consecutive participants attending screening (Day 1) and baseline (Day 2) visits between July 2011 and December 2011. All participants met the American College of Rheumatology criteria for OA; had radiographic knee OA, as defined by Kellgren-Lawrence grade 2 or 3; and knee synovitis, defined by a synovial pouch depth greater than 2.0 mm measured by ultrasound. All participants were also required to have knee pain symptoms, defined as a WOMAC Osteoarthritis Index (version 3.1, 5-point Likert) pain subscore > 2 at the beginning of their first visit (Day 1). All participants completed 4 trials on 2 separate days, 7 to 21 days apart (8 trials total). Each day was divided into 2 sessions, which each involved 2 walking trials. Day 1 contained sessions 1 (trial 1 and 2) and session 2 (trial 3 and 4) and Day 2 contained session 3 (trial 5 and 6) and session 4 (trial 7 and 8). All trials were administered by the same investigator following a standardized script and protocol. We compared walk times between trials with Wilcoxon signed-rank tests. We also calculated Spearman correlation coefficients to assess the relationship between sessions. Finally, smallest detectable differences (SDD) were calculated to estimate the sensitivity of the 20-meter walk test. Results: Participants were 53% female, 67% (n 1⁄4 10) Caucasian, on average 61.0 7.8 years of age and had a mean body mass index of 28.9 5.4 kg/m2. Twelve participants (80%) had Kellegren-Lawrence Grade 1⁄4 3. WOMAC pain scores were 5.3 1.3 on Day 1 and 4.9 2.0 on Day 2. The figure depicts walk times across trials. We found that walking times in the first session were slower than the second session (median difference 1⁄4 0.53 seconds, -0.04 m/s; Table). We also found that the correlation between session 1 and sessions 3 and 4 were lower than the correlations between session 2 and sessions 3 and 4 (Table). Therefore, we considered the first session of each day a practice session and calculated the SDD between the second session of each day (session 2 and 4). SDD were -2.59 seconds (walking slower) and 1.65 seconds (walking faster). There was a potential systematic bias of participants walking slower during the second session on Day 2 compared to the second session of Day 1 (10 [67%] participants walked slower in session 4 compared to session 2; based on differences below zero). Conclusions:We found that the average of the first two 20-meter walk times did not agree with subsequent average walk times among participants with knee OA. Therefore, practice trials may be advised prior to a measuring a participants walk time. Despite concerns about thewalk times of session 1, the following sessions were reliable and had good agreement. Finally, changes in walk time between -2.59 seconds (walking slower) and 1.65 seconds (walking faster) should be considered within the range of normal variability of 20-meter walking speed.

The Multisurface Obstacle Test for Older Adults (MSOT): development and reliability of a novel test for older adults

Abstract Locomotion is an essential component of independence and well-being at old age. Performance deficits in the gait of older adults most often become evident on multisurface and varying terrains. Research results substantiate that falls occur in everyday movement situations that are characterized by instability. A test track, the Multisurface Obstacle Test for Older Adults (MSOT), was developed to diagnose individual performance. The 10-m track consists of different obstacles and varying surfaces, which represent everyday movement situations in a compact way. Twenty-nine untrained, healthy older adults (11 men, 18 women) were tested on three different days at 1-week intervals in a test–retest design by the same conductor. Mean age of the participants was 68.8 ± 5.3 years with a mean body mass index of 24.4 ± 2.5 kg/m2. The measured outcome variable was the required time (seconds) on the MSOT. The feasibility for the tested sample of untrained older adults was very good. The MSOT was undertaken safely by the participants, and no falls occurred. The range of the mean for time was between 8.12 ± 1.53 s and 9.00 ± 1.62 s. Regarding intertrial reliability, mean differences (MD) of −3.39 to −5.52 % and coefficients of variation (CV) of 2.72 to 4.19 % between the first and second trials and MD of −0.69 to −0.85 % and CV of 2.57 to 4.54 % over the three test sessions were observed. The correlation coefficients between the sessions were .92–.98. There were significant differences (p &lt; .05) between the first and second trials of each session and between the first and second sessions. The smallest detectable differences (SDD) revealed that a small improvement is enough to detect changes in performance in the MSOT. Selecting tasks from real-life situations of older adults contributes to substantiate practical usability of the MSOT. The measured time on the MSOT showed high relative and absolute reliability in the target group of older adults between 60 and 80 years.

Reproducibility of tender point examination in chronic low back pain patients as measured by intrarater and inter-rater reliability and agreement: a validation study

ObjectivesTo evaluate the reliability and agreement of digital tender point (TP) examination in chronic low back pain (LBP) patients.DesignCross-sectional study.SettingsHospital-based validation study.ParticipantsAmong sick-listed LBP patients referred from general practitioners for...

Intra- and Inter-Rater Reliability of the Mini-Balance Evaluation Systems Test in Individuals with Stroke

Objective: The aim of this study was to assess intra- and inter-rater reliability of the ‘The Mini-Balance Evaluation Systems Test (Mini-BESTest)’ in adults with stroke, based on video recordings of their test performances. Methods: We included 24 adults with stroke classified at four different ambulatory levels, ranging from the ability to ambulate within the household only, to normal ambulation. Mini-BESTest performance of the participants were filmed and then scored by three raters twice, with four weeks between the sessions. None of the raters had used the test prior to the study, but attended a three-hour training session to become familiar with the test and scoring instructions just before study-start. Relative reliability was investigated for by calculating intraclass correlation coefficients (ICC1.1 and ICC3.1). Absolute reliability was assessed by calculating within-subject standard deviation (sw) and smallest detectable difference (SDD). For each individual items of the Mini-BESTest, Cohen’s kappa (k) was calculated. Results: The study showed that the Mini-BESTest had excellent intra-rater reliability (ICC1.1=0.94−0.99 and ICC3.1=0.97−0.99) and inter-rater reliability (ICC1.1=0.97−0.99 and ICC3.1=0.97−0.99). Kappa values for the individual items ranged between 0.21 and 1.00. The majority of items (intra-rater=88%, inter-rater=78%) showed very good or good agreement. The smallest detectable change at 95% confidence interval was ≤4 points for intra-rater assessments and ≤ 3 points for inter-rater assessments. Conclusions: We conclude that the reliability of the Mini-BESTest based on video recordings of adults with stroke is excellent, even though the ratings are performed by novice assessors.

Reliability and responsiveness of dynamic contrast-enhanced magnetic resonance imaging in rheumatoid arthritis

Objectives: To investigate the responsiveness to treatment and the reliability of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in rheumatoid arthritis (RA) knee joints.Methods: DCE-MRI was performed in 12 clinically active RA knee joints before and 1, 7, 30, and 180 days after intra-articular injection with 80 mg methylprednisolone. Using semi-automated image processing software, DCE-MRI parameters, including the initial rate of enhancement (IRE) and maximal enhancement (ME), were generated for three regions of interest (ROIs): ‘Whole slice’, ‘Quick ROI’, and ‘Precise ROI’. The smallest detectable difference (SDD), the smallest detectable change (SDC), and intra- and inter-reader intraclass correlation coefficients (ICCs) were used to assess the reliability of DCE-MRI. Responsiveness to treatment was assessed by the standardized response mean (SRM).Results: In all patients clinical remission of the knee was achieved at day 7. All DCE-MRI parameters decreased from day 0 to day 7. Using the Quick and Precise ROI methods, respectively, IRE decreased by 63% and 69%, ME decreased by 11% and 11%, Nvoxel decreased by 55% and 57%, and IRE × Nvoxel decreased by 84% and 85%. The intra- and inter-reader ICCs were very high (0.96–1.00). The decrease in DCE-MRI parameters was larger than the SDC for all patients. SRM was large for all parameters, ranging from –1.04 to –2.40. When the Whole slice ROI method was used, no parameters were responsive to treatment.Conclusions: DCE-MRI analysed using semi-automatic software is a reliable and responsive tool for assessing treatment in RA knees joints. Rough manual delineation of the joint to omit enhancement artefacts is necessary.

Smallest detectable differences in clinical functional temporomandibular joint examination variables in juvenile idiopathic arthritis

Temporomandibular joint (TMJ) arthritis in juvenile patients may interfere with optimal joint function and mouth opening patterns. Clinical assessment of maximal mouth opening capacity, laterotrusion and protrusion is critical to TMJ arthritis diagnosis, treatment choice and evaluation of a therapeutic intervention. The aim of the study was to determine the smallest minimal threshold at which differences in maximal mouth opening capacity, laterotrusion, and protrusion between two consecutive observations can be determined. Department of Orthodontics, University of Aarhus, Denmark. Forty-two consecutive patients with juvenile idiopathic arthritis. Two experienced dentists used a calibrated metallic ruler to measure maximal mouth opening capacity, laterotrusion, and protrusion. Each measurement was carried out thrice by each observer. Intra- and inter-observer variation and the smallest detectable difference were calculated for each variable. The smallest detectable differences were as follows: maximal mouth opening capacity 4.9 mm, laterotrusion 2.4 mm, and protrusion 2.8 mm (one observer and one measurement). These differences declined when measurements were repeated; maximal mouth opening capacity 3.3 mm, laterotrusion 1.4 mm, and protrusion 1.8 mm (two observers with three measurements each). We found no support for a relationship between measurement variation and patient age, measurement variation and TMJ pain, or between measurement variation and previous/current TMJ arthritis. The importance of the implementation of a standardized measurement protocol is emphasized including repeated measurements to reduce the smallest detectable difference.

Effect of Subject Restraint and Resistance Pad Placement on Isokinetic Knee Flexor and Extensor Strength

Background:In clinical practice, several subject restraint and resistance pad placement variations are used when an isokinetic knee flexion/extension test is performed. However, it is unknown if these variations affect the outcome measures. The aims of this study were to determine if these setup variations affect isokinetic outcomes and to establish the smallest detectable difference for these setup variations.Hypothesis:Variation in isokinetic setup affects outcome measures.Study Design:Cross-sectional repeated-measures crossover study.Methods:Ten recreationally active adult men were examined with isokinetic dynamometry on 4 separate days. In the first 3 days, fully strapped and trunk-unstrapped testing was conducted with the resistance pad placed distally on the shin. On days 1 and 3, the unstrapped condition was performed first, followed by the strapped condition. On day 4, the resistance pad was placed proximal on the shin (anterior cruciate ligament testing).Results:There were no within-condition differences for days 1, 2, or 3 for the strapped and unstrapped conditions (P > 0.05). Between-condition comparisons were significant (eg, quadriceps peak torque, P < 0.001; hamstring peak torque, P = 0.043) for the strapped, unstrapped, and proximal resistance pad placement conditions. The strapped condition generally showed the largest torques, and the unstrapped, the least. The smallest detectable differences were relatively large (eg, quadriceps peak torque strapped = 20.6%). The greatest intraclass correlation values were found when strapped.Conclusions:Subject setup significantly influences isokinetic outcome measures at the knee. Since the strapped condition demonstrated the greatest repeatability, it is recommended. The smallest detectable differences were relatively high for all variables and should be considered in the interpretation of the effect size of interventions.Clinical Relevance:Subject setup strapping must be considered when investigating test-retest values or when comparing subjects after isokinetic testing at the knee. The fully strapped condition has the best repeatability and highest torque values.

Effectiveness of manual therapy and home physical therapy in patients with temporomandibular disorders: A randomized controlled trial

The purpose of this study was to compare the short-term effectiveness of home physical therapy (HPT) alone with that of manual therapy (MT) in conjunction with home physical therapy (MT-HPT) performed for four weeks in patients with temporomandibular disorders (TMD). Forty subjects (nine males and 31 females; age, 18-72 years) with TMD were randomly divided into two groups: HPT (n=20; five males and 15 females; mean age, 34.8±12.4 years) and MT-HPT (n=20; four males and 16 females; mean age, 37.0±14.6 years). Pain intensity was evaluated at rest and with stress using a visual analogue scale (VAS). Pain-free maximum mouth opening (MMO) was also evaluated. Mean change score (MCS) in VAS and the smallest detectable difference (SDD) in pain-free MMO were measured over time. The results were analysed by MANOVA to evaluate the effects of treatment over time. At baseline, the groups did not differ from each other with respect to VAS scores and pain-free MMO (p>0.05). Within each group, VAS with stress decreased (p<0.001) and pain-free MMO increased (p<0.001) over time. Between groups, both time*treatment effect and treatment effect were significant for VAS with stress (p<0.001); however, only time*treatment effect was significant for pain-free MMO (p=0.009). In the MT-HPT group, MCS for VAS with stress was 91.3% and SDD for pain-free MMO was 10mm. Our results suggest that a four-week period of MT-HPT has a clinically significant effect on both pain and pain-free maximum mouth opening in patients with TMD.

Test–retest reliability and developmental evolution of the 6-min walk test in Caucasian boys aged 5–12years

The 6-min walk test (6MWT) assesses functional capacity and has been used as outcome measure in therapeutic studies in childhood neuromuscular disorders. The objectives were to evaluate test-retest reliability of the 6MWT and to generate normative data for healthy boys aged 5-12 years. Ninety boys (mean age 8 years 10 months) were recruited over four age subcategories (5-6, 7-8, 9-10, 11-12 years). Mean 6MWT distance and velocity (±standard deviation) for the total group were 555.5±93 m and 92.6±16.6 m/min. The 6MWT distance increased significantly with age. Test-retest reliability (mean interval 12 days) was very high for the total group (ICC>0.95) and for all age subcategories (ICC>0.80) a moderately high reliability (ICC>0.75) was found from 3 min onwards for each age subcategory. There was a mean difference of 5.2 m between test and retest without systematic bias. The standard error of measurement and smallest detectable difference were 20.7 and 57.4 m, respectively. These findings demonstrate the reliability of the 6MWT in young children, underscore its evolution with age, and indicate that a shorter version of the test is also reliable.

Reliability and Longitudinal Validity of Computer-assisted Methods for Measuring Joint Damage Progression in Subjects with Rheumatoid Arthritis

To compare the metric properties of a computer-assisted erosion segmentation volume measurement with scoring using the Rheumatoid Arthritis Magnetic Resonance Imaging Score (RAMRIS) in a longitudinal cohort of patients with rheumatoid arthritis (RA). Thirty-two sets of baseline and 2-year followup magnetic resonance imaging (MRI) of metacarpal phalangeal 2-5 joints of patients with RA were scored using RAMRIS and segmented using OSIRIS software. The smallest detectable difference (SDD), standardized response mean (SRM), and paired t-test were used to evaluate the sensitivity to change. Eleven of the 32 patients' MRI were segmented by both readers to evaluate interreader agreement. The 28-joint Disease Activity Score (DAS28) and Sharp erosion scores further evaluated construct and longitudinal validity. Reliability of erosion progression by computer-assisted volume measurement was superior to RAMRIS [intrareader interclass correlation coefficient (ICC) 0.97 (0.94-0.99) vs 0.52 (0.22-0.73)] and interreader ICC of volume measurement was 0.85 (0.53-0.96). Computer-assisted volume measurements identified 10 of 32 patients who progressed more than the SDD progression, whereas RAMRIS identified only 4 of 32 patients (p = 0.0013). By a paired t-test, however, all MRI measures progressed significantly over 2 years (irrespective of treatment arm) and there was little difference by SRM. Construct correlational validity of the MRI methods was 0.47-0.90 for status scores and 0.33-0.81 for progression. There was no relationship between the average DAS28 and erosion progression by any imaging method. Computer-assisted measurement of erosion volume has good performance metrics. It had excellent intrareader and interreader reliability and was more sensitive to change than RAMRIS in this group of patients. www.ClinicalTrials.gov, NCT00451971.

Detection of progression of radiographic joint damage in case of very early osteoarthritis: sensitivity to change of quantitative analysis compared to qualitative grading

For more tailored treatment of osteoarthritis it is worthy to identify different subpopulations early in the disease. Objective of this study is to evaluate whether the sensitivity to detect progression of radiographic features, which may add to this identification, can be improved by quantitative measurement (using Knee Images Digital Analysis; KIDA), compared to qualitative grading (according to the Altman atlas). Among individuals with early signs related to osteoarthritis (Cohort Hip and Cohort Knee, Check) symptomatic knees (n=1082) were selected. Standardized baseline and two-year follow-up radiographs were evaluated for joint space narrowing, osteophyte formation, and bone density changes using KIDA measurement and Altman scales. Sensitivity to change was determined by calculating the standardized response mean (SRM). For all distinct KIDA parameters, the smallest detectable difference was calculated to define radiographic changes at the individual level. The percentage of knees that changed was compared between KIDA measurement and Altman grading. Also agreement between both methods was evaluated. Studying radiographic progression in knees with early signs related to osteoarthritis showed, for all KIDA and Altman parameters, a small SRM and radiographic change in a small percentage of knees. The sensitivity to detect radiographic progression was similar for KIDA measurement and Altman grading. However, agreement between the Altman and KIDA method was limited (kappa ≤0.20). Although sensitivity to change is limited, similar for KIDA measurement and Altman grading, this may not exclude that measurement of separate features might be useful to distinguish subpopulations of osteoarthritis later in the disease.

Corneal endothelial cell changes 5 years after laser in situ keratomileusis: Femtosecond laser versus mechanical microkeratome

To compare corneal endothelial cell density (ECD) and morphology between flap creation with a femtosecond laser and flap creation with a mechanical microkeratome 5 years after laser in situ keratomileusis (LASIK). Mayo Clinic, Rochester, Minnesota, USA. Prospective randomized masked paired-eye study. In this study of LASIK for myopia or myopic astigmatism, fellow eyes were randomized by ocular dominance to flap creation by a femtosecond laser or by a mechanical microkeratome. Central endothelial images were analyzed before and 3 years and 5 years after LASIK; endothelial cell variables were compared between treatments at each examination. Relationships between endothelial cell loss and contact lens wear, residual bed thickness, and preoperative refractive error were evaluated. There were no differences in the ECD, percentage of hexagonal cells, or coefficient of variation of cell area between treatments at any examination (all P = .99); the smallest detectable differences were 120 cells/mm(2), 5%, and 2%, respectively. The mean annual rate of corneal endothelial cell loss was -0.1% ± 1.2% (SD) and -0.1% ± 1.0% for the femtosecond laser and the mechanical microkeratome, respectively. Endothelial cell loss was not associated with contact lens wear, residual bed thickness, or preoperative refractive error. The energy delivered to the cornea during femtosecond laser flap creation did not affect the corneal endothelium 5 years after LASIK when compared with flap creation with a mechanical microkeratome. Corneas that have had either method of flap creation could be accepted as donor tissue for endothelial keratoplasty from the standpoint of endothelial health. No author has a financial or proprietary interest in any material or method mentioned.

Orofacial Symptoms Related to Temporomandibular Joint Arthritis in Juvenile Idiopathic Arthritis: Smallest Detectable Difference in Self-reported Pain Intensity

Temporomandibular joint (TMJ) inflammation in patients with juvenile idiopathic arthritis (JIA) may lead to mandibular growth disturbances and interfere with optimal joint and muscle function. Orofacial symptoms are common clinical findings in relation to TMJ arthritis in adolescence. Knowledge about their clinical manifestation is important for TMJ arthritis diagnosis, treatment choice, and outcome evaluation. The aim of our prospective observational study was to evaluate and describe the frequency, the main complaints, and the localization of TMJ arthritis-related orofacial symptoms. The smallest detectable differences (SDD) for minimal, average, and maximal pain were estimated. Thirty-three patients with JIA and arthritis-related orofacial symptoms in relation to 55 affected TMJ were included in our questionnaire study (mean age 14.11 yrs). Calculation of the SDD was based on a duplicate assessment 45 min after the first questionnaire was completed. The majority of the patients had common orofacial symptoms during mastication and maximal mouth opening procedures. Persistent orofacial symptoms were rare. The TMJ area in combination with the masseter muscle region was the orofacial region where symptoms were most common. The SDD for minimal, average, and maximal pain were between 10 and 14 mm on a visual analog scale. Our study offers new knowledge about TMJ arthritis-related orofacial symptoms that may aid diagnosis and clinical decision-making. We suggest that TMJ arthritis-related orofacial symptoms could be understood as products of the primary TMJ inflammation in combination with secondary myogenic and functional issues.