Establishing the minimum clinically important difference of the Quality of Life in Childhood Epilepsy Questionnaire.

OBJECTIVE: To estimate the minimum clinically important difference (MCID) for the parent-reported 55-item Quality of Life in Childhood Epilepsy Questionnaire (QOLCE-55) and its shortened 16-item version, QOLCE-16. METHODS: Data came from 74 children with epilepsy (CWE) (ages 4-10, mean age = 8 [SD = 1.8]) enrolled in the Making Mindfulness Matter in Epilepsy (M3-E) trial, a pilot, parallel randomized-controlled trial of a mindfulness-based intervention. Both anchor-based and distribution-based methods were used to estimate MCID values for the QOLCE-55 and QOLCE-16. For the anchor-based approach, the Patient Centered Global Ratings of Change (PCGRC) scale and linear regression analysis were used to estimate the MCID. For the distribution-based approach, .5 SD of the health-related quality of life (HRQOL) change score distribution was used to estimate the MCID. RESULTS: For the QOLCE-55, the MCID obtained using an anchor-based approach was 10 points and using a distribution-based method was 6 points. For the QOLCE-16, the MCID obtained using an anchor-based method was 13 points and using a distribution-based method was 7 points. SIGNIFICANCE: This is the first study to estimate MCID values for the QOLCE-55 and the QOLCE-16. It has been well documented that CWE are at risk of experiencing psychological, behavioral, and cognitive impairments, which can negatively impact their HRQOL. Reporting MCID values for the QOLCE-55 and QOLCE-16 is important in determining whether changes in HRQOL observed are meaningful to CWE themselves, as a key factor in shaping the nature of epilepsy care delivered.

Calculation of the minimum clinically important difference (MCID) using different methodologies: case study and practical guide.

INTRODUCTION: Establishing thresholds of change that are actually meaningful for the patient in an outcome measurement instrument is paramount. This concept is called the minimum clinically important difference (MCID). We summarize available MCID calculation methods relevant to spine surgery, and outline key considerations, followed by a step-by-step working example of how MCID can be calculated, using publicly available data, to enable the readers to follow the calculations themselves. METHODS: Thirteen MCID calculations methods were summarized, including anchor-based methods, distribution-based methods, Reliable Change Index, 30% Reduction from Baseline, Social Comparison Approach and the Delphi method. All methods, except the latter two, were used to calculate MCID for improvement of Zurich Claudication Questionnaire (ZCQ) Symptom Severity of patients with lumbar spinal stenosis. Numeric Rating Scale for Leg Pain and Japanese Orthopaedic Association Back Pain Evaluation Questionnaire Walking Ability domain were used as anchors. RESULTS: The MCID for improvement of ZCQ Symptom Severity ranged from 0.8 to 5.1. On average, distribution-based methods yielded lower MCID values, than anchor-based methods. The percentage of patients who achieved the calculated MCID threshold ranged from 9.5% to 61.9%. CONCLUSIONS: MCID calculations are encouraged in spinal research to evaluate treatment success. Anchor-based methods, relying on scales assessing patient preferences, continue to be the "gold-standard" with receiver operating characteristic curve approach being optimal. In their absence, the minimum detectable change approach is acceptable. The provided explanation and step-by-step example of MCID calculations with statistical code and publicly available data can act as guidance in planning future MCID calculation studies.

Should We Wait for Bone-on-Bone Arthritis? Equivalent Clinical Outcomes in Patients Requiring Advanced Imaging Before Primary Total Hip Arthroplasty.

BACKGROUND: Plain radiographs remain the standard for diagnosing osteoarthritis (OA). Total hip arthroplasty (THA) is generally offered only for advanced OA by plain radiographs. Advanced imaging is used as an adjunct to assess OA severity in cases of progressive symptoms with less advanced OA by plain radiographs. The objective of this study was to compare outcomes following THA in patients who have advanced OA visualized by plain radiographs to patients who have less severe OA visualized by plain radiographs. METHODS: From February 2016 to February 2020, 93 patients who had Kellgren-Lawrence (KL) grade 0 to 2 OA and underwent THA were identified. The median age was 65 years, and 55% were women. They were matched 1:3 to patients who underwent THA for KL 4 OA based on age, sex, body mass index, and Charlson Comorbidity Index. The primary outcome was achievement of the Hip Injury and Osteoarthritis Outcome Score for Joint Replacement (HOOS JR) minimum clinically important difference, substantial clinical benefit, and patient-acceptable symptom state at 1 year postoperatively. RESULTS: There was no difference between the KL 0 to 2 and KL 4 cohorts in the achievement of HOOS JR minimum clinically important difference (86 versus 85.6%, P = .922), substantial clinical benefit (81.7 versus 80.2%, P = .751), or patient-acceptable symptom state (89.2 versus 85.6%, P = .374). The KL 0 to 2 cohort had a similar improvement in their 2-year HOOS JR (42.5 versus 38.6, P = .019). CONCLUSIONS: In this series, there was no difference in outcomes following primary THA between patients who have severe OA on plain radiographs (KL 4) compared to those who have less severe OA (KL 0 to 2). In the setting of severe symptoms and the absence of advanced OA on radiographs, advanced imaging can be used to guide treatment and select patients who could benefit from THA.

Correlating Evoked Electromyography and Anatomic Factors During Spinal Cord Stimulation Implantation With Short-Term Outcomes.

INTRODUCTION: We examine ways intraoperative neuromonitoring during spinal cord stimulation (SCS) varies between a high-resolution investigational SCS (HR-SCS) paddle and a commercial paddle. Furthermore, the presence of evoked motor responses (eg, electromyography [EMG]) in painful regions during surgery is correlated to outcomes. MATERIALS AND METHODS: We used HR-SCS to assess EMG response from 18 patients (NCT05459324). Maximum percentage change in root mean squared (maxRMS) EMG values was determined. Correlations were performed with magnetic resonance imaging measurements and patient outcomes collected preoperatively and at three months (numerical rating scale [NRS], McGill Pain, Beck Depression Inventory, Oswestry Disability Index [ODI], and Pain Catastrophizing Score). RESULTS: Of the 18 patients (12 women to six men; mean age 56 years; eight with neuropathic pain, eight with persistent spinal pain syndrome, two with complex regional pain syndrome), nine had a response at three months based on 50% reduction in NRS, 14 by achieving minimal clinically important difference (MCID) on NRS, and 11 by reaching MCID on ≥three outcome metrics. The anterior posterior diameter (APD) of the spinal column at level of testing correlated with all three responses (p < 0.05). We examined RMS at muscles correlating with individual patient pain distributions and found correlations between RMS and MCID NRS and MCID ODI (p < 0.05). maxRMS in abductor hallucis correlated with improvement in NRS and ODI across the group (p < 0.05). CONCLUSIONS: We found that eliciting EMGs over the painful areas during surgery caused alleviation of pain intensity and disability. Obtaining stimulation of abductor hallucis (AH) was more predictive of pain improvement than any other muscle group, and APD alone correlated with improvements in pain intensity and holistic outcomes. These pilot data suggest that implanters should consider APD and EMG responses from painful regions and AH during surgery.

When does patient function "Plateau" after total joint arthroplasty? A cohort study.

PURPOSE: With over 100,000 procedures completed per year, hip and knee arthroplasty are two of the most common surgical procedures performed in Canada. There has been literature indicating that patient reported outcome measures (PROM) will start to plateau between six and 12 months. The purpose of this paper was to analyze the trajectory of PROMs following total hip and knee arthroplasty (THA and TKA), as well as assess the impact of any potential confounders on this trajectory. The central research question was: At what point do PROMS plateau among patients that undergo elective THA and TKA? METHODS: This study was a retrospective analysis of data from a prospective database. Patients were eligible if they had undergone an elective, primary THA/TKA with Oxford Scores recorded pre-operatively, and at least at two of the following four time points: six weeks, six months, one year, and two years. RESULTS: Mean pre-operative Oxford scores were 18.0 (7.8) for THA, and 20.1 (7.5) for TKA. For both THA and TKA, there were statistically significant interval improvements in Oxford scores from six weeks [THA: 33.8 (7.9)/TKA: 28.7 (7.8)] to six months [THA: 40.2 (7.3)/TKA: 35.9 (8.3)], and from six months to one year [THA: 41.0 (7.3)/TKA: 37.3 (8.4)], but not from one to two years [THA: 40.0 (8.5)/TKA: 36.4 (9.6)]. CONCLUSIONS: Patients undergoing either primary THA or TKA can expect clinically meaningful improvements in the first six months after surgery. Beyond this time point, there is a plateau in PROMs. These findings are important for both setting patient expectations in pre-operative discussions, and allowing surgeons to have a realistic understanding of their patients' expected post-operative course.

Time to achievement of minimum clinically important difference after lumbar decompression.

OBJECTIVE: The objective of this study is to examine factors associated with delayed time to achieve minimum clinically important difference (MCID) in patients undergoing lumbar decompression (LD) for the Patient-Reported Outcomes (PROs) of Oswestry Disability Index (ODI), Visual Analog Scale (VAS) back, and VAS leg pain. METHODS: Patients undergoing LD with preoperative and postoperative ODI, VAS back, and VAS leg scores were retrospectively reviewed from April 2016 to January 2021. MCID values from previously established studies were utilized to determine MCID achievement. Kaplan-Meier survival analysis determined the time to achieve MCID. Hazard ratios from multivariable Cox regression were utilized to determine the preoperative factors predictive of MCID achievement. RESULTS: Three-hundred and forty-three patients were identified undergoing LD. Overall MCID achievement rates were 67.4% for ODI, 67.1% for VAS back, and 65.0% for VAS leg. The mean time in weeks for MCID achievement was 22.52 ± 30.48 for ODI, 18.90 ± 27.43 for VAS back, and 20.96 ± 29.81 for VAS leg. Multivariable Cox regression revealed active smoker status, preoperative Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF), ODI, VAS Back, and VAS Leg (HR 1.03-2.14) as predictors of early MCID achievement, whereas an American Society of Anesthesiologist (ASA) classification of 2, Black ethnicity, workers' compensation, private insurance, and diagnosis of foraminal stenosis were predictors of late MCID achievement (HR 0.34-0.58). CONCLUSION: Most patients undergoing LD achieved MCID within 6 months of surgery. Significant factors for early MCID achievement were active smoking status and baseline PROs. Significant factors for late MCID achievement were ASA = 2, Black ethnicity, type of insurance, and foraminal stenosis diagnosis. These factors may be considered by surgeons in setting patient expectations.

Establishing minimum clinically important difference for patient-reported outcome measures in patients undergoing lateral lumbar interbody fusion.

BACKGROUND: The minimum clinically important difference (MCID) has not been established in lateral lumbar interbody fusion (LLIF). Our study aims to establish MCID for patient-reported outcome measures (PROMs) of physical function and pain for LLIF through anchor-based and distribution-based approaches. METHODS: Patients undergoing LLIF with preoperative and 6-month postoperative Oswestry Disability Index (ODI) scores were identified. PROMs of Patient-Reported Outcome Measurement Information System Physical Function (PROMIS-PF), 12-Item Short Form Physical Component Score (SF-12 PCS), Veterans RAND 12-Item Short Form Physical Component Score (VR-12 PCS), visual analog scale (VAS) back, and VAS leg were collected at preoperative and 6-month postoperative time points. Anchor-based MCID calculations were average change, minimal detectable change, change difference, receiver operating characteristic curve, and cross-sectional analysis using ODI as the anchor. Distribution-based calculations were standard error of measurement, reliable change index, effect size, and 0.5 ∗ ΔSD. RESULTS: Fifty patients were included. Anchor-based approaches MCID ranges were PROMIS-PF 1.1-9.6, SF-12 PCS 6.4-16.5, VR-12 PCS 5.9-12.9, VAS Back 1.4-4.6, and VAS Leg 1.3-4.3. The area under curve for receiver operating characteristics (ROC) analysis ranged from 0.63 to 0.71. Distribution-based MCID ranges were PROMIS-PF 1.4-4.5, SF-12 PCS 1.9-12.7, VR-12 PCS 2.0-6.6, VAS Back 0.4-1.4, and VAS Leg 0.5-2.0. CONCLUSION: MCID thresholds varied widely depending on the calculation method. The closest to (0,1) ROC approach was the most clinically appropriate MCID calculation. The corresponding MCID values for LLIF were PROMIS-PF at 7.8, SF-12 PCS at 6.4, VR-12 PCS at 9.3, VAS Back at 4.6, and VAS Leg at 4.3.

Impact of preoperative symptom duration in patients undergoing lateral lumbar interbody fusion.

BACKGROUND: Few studies have examined the influence of preoperative symptom duration on clinical outcomes in patients undergoing lateral lumbar interbody fusion (LLIF) for degenerative conditions. METHODS: Patients undergoing LLIF presenting with radiculopathy and/or neurogenic claudication were separated into two groups: preoperative symptom duration < 1-year (shorter duration) versus duration ≥ 1-year (longer duration). Patients undergoing surgery for trauma/malignancy/infection were excluded. Patient-reported outcome measures (PROMs) of Patient-Reported Outcomes Measurement Information System-Physical Function (PROMIS-PF), 12-Item Short Form Physical/Mental Component Score (SF-12 PCS/MCS), Patient Health Questionnaire-9 (PHQ-9), visual analog scale (VAS) back/leg, and Oswestry Disability Index (ODI) were collected at preoperative and postoperative time points. RESULTS: Eighty-two total patients, with 34 shorter-duration patients, were identified after propensity score matching for demographics. Longer-duration patients had higher estimated blood loss. All patients reported significant improvement in physical function, mental function, pain, and disability in at least one postoperative time point, except for SF-12 MCS in the shorter duration cohort. The longer duration cohort had higher MCID achievement in 12-week VAS back. CONCLUSION: Patients undergoing LLIF demonstrated significant postoperative improvement in physical function, mental function, pain, and disability outcomes independent of preoperative symptom duration. Both cohorts, when compared by preoperative symptom duration, demonstrated similar postoperative PROM scores. Patients with longer preoperative symptom duration had higher 12-week leg pain MCID achievement. These findings suggest that delayed time to surgery may not lead to inferior clinical outcomes in patients undergoing LLIF for degenerative conditions.

Patients aged 50-75 years take longer to achieve the patient acceptable symptom state than patients aged 20-34 years following primary hip arthroscopy for femoroacetabular impingement syndrome.

PURPOSE: Though an increasing number of adults older than 50 years are undergoing hip arthroscopy for treatment of Femoroacetabular Impingement Syndrome (FAIS), it is unclear how their timeline for functional outcome improvement compares to that of younger patients. The purpose of this study was to assess the impact of age on time to achieving the Minimum Clinically Important Difference (MCID), Substantial Clinical Benefit (SCB), and Patient Acceptable Symptom State (PASS) following primary hip arthroscopy for FAIS. METHODS: A retrospective comparative single-surgeon cohort study of primary hip arthroscopy patients with minimum 2-year follow-up was conducted. Age categories were 20-34 years, 35-49 years, and 50-75 years. All subjects completed the modified Harris Hip Score (mHHS) prior to surgery and at 6-month, 1-year, and 2-year follow-up. MCID and SCB cutoffs were defined as pre-to-postoperative increases in mHHS by ≥ 8.2 and ≥ 19.8, respectively. PASS cutoff was set at postoperative mHHS ≥ 74. Time to achievement of each milestone was compared using interval-censored survival analysis. The effect of age was adjusted for Body Mass Index (BMI), sex, and labral repair technique using an interval-censored proportional hazards model. RESULTS: Two hundred eighty-five patients were included in the analysis with 115 (40.4%) aged 20-34 years, 92 (32.3%) aged 35-49 years, and 78 (27.4%) aged 50-75 years. There were no significant differences between groups in time to achievement for the MCID (n.s.) or SCB (n.s.). However, patients in the oldest group had significantly longer time to PASS than those in the youngest group, both in the unadjusted analysis (p = 0.02) and after adjusting for BMI, sex, and labral repair technique (HR 0.68, 95% CI 0.48-0.96, p = 0.03). CONCLUSION: Achievement of the PASS, but not the MCID or SCB, is delayed among FAIS patients aged 50-75 years who undergo primary hip arthroscopy compared to those aged 20-34 years. Older FAIS patients should be counseled appropriately about their longer timeline to achieving hip function comparable to their younger counterparts. LEVEL OF EVIDENCE: III.

Should responder analyses be conducted on continuous outcomes?

Continuous outcomes are often dichotomized to classify trial subjects as responders or nonresponders, with the difference in rates of response between treatment and control defined as the "responder effect." In this article, we caution that dichotomization of continuous interval outcomes may not be best practice. Defining clinical benefit or harm for continuous interval outcomes as the difference between the means of treatment and control, that is, the "continuous treatment effect," we examine the case where treatment and control outcomes are normally distributed and differ only in location. For this case, continuous treatment effects may be considered clinically relevant if they exceed a prespecified minimum clinically important difference. In contrast, using minimum clinically important differences as dichotomization thresholds will not ensure clinically relevant responder effects. For example, in some situations, increasing the threshold may actually relax the criterion for effectiveness by increasing the calculated responder effect. Using responder effects to quantitatively assess benefit or risk of investigational drugs for continuous interval outcomes presents interpretational challenges. In particular, when the dichotomization threshold is halfway between the treatment and control outcome means, the responder effect is at a maximum with a magnitude monotonically related to the number of standard deviations between the mean outcomes of treatment and control. Large responder effect benefits may therefore reflect clinically unimportant continuous treatment effects amplified by small standard deviations, and small responder effect risks may reflect either clinically important continuous treatment effects minimized by large standard deviations, or selection of a dichotomization threshold not providing maximum responder effect.

AFOs Improve Stride Length and Gait Velocity but Not Motor Function for Most with Mild Cerebral Palsy.

Ankle-foot orthoses (AFOs) are prescribed to children with cerebral palsy (CP) in hopes of improving their gait and gross motor activities. The purpose of this retrospective study was to examine if clinically significant changes in gross motor function occur with the use of AFOs in children and adolescents diagnosed with CP (Gross Motor Function Classification System levels I and II). Data from 124 clinical assessments were analyzed. Based on minimum clinically important difference (MCID), 77% of subjects demonstrated an increase in stride length, 45% of subjects demonstrated an increase in walking velocity, and 30% demonstrated a decrease in cadence. Additionally, 27% of the subjects demonstrated increase in gait deviation index (GDI). Deterioration in gait was evident by decreases in walking speed (5% of subjects), increases in cadence (11% of subjects), and 15% of subjects demonstrated decreases in gait deviation index. Twenty-two percent of subjects demonstrated no change in stride lengths and one participant demonstrated a decrease in stride length. However, AFOs improved Gross Motor Function Measure (GMFM) scores for a minority (10%) of children with mild CP (GMFCS level I and II), with 82-85% of subjects demonstrating no change in GMFM scores and 5-7% demonstrating decrease in GMFM scores.

Validation and minimum important difference of the UCSD Shortness of Breath Questionnaire in fibrotic interstitial lung disease.

RATIONALE: The University of California, San Diego Shortness of Breath Questionnaire (UCSDSOBQ) is a frequently used domain-specific dyspnea questionnaire; however, there is little information available regarding its use and minimum important difference (MID) in fibrotic interstitial lung disease (ILD). We aimed to describe the key performance characteristics of the UCSDSOBQ in this population. METHODS: UCSDSOBQ scores and selected anchors were measured in 1933 patients from the prospective multi-center Canadian Registry for Pulmonary Fibrosis. Anchors included the St. George's Respiratory Questionnaire (SGRQ), European Quality of Life 5 Dimensions 5 Levels questionnaire (EQ-5D-5L) and EQ visual analogue scale (EQ-VAS), percent-predicted forced vital capacity (FVC%), diffusing capacity of the lung for carbon monoxide (DLCO%), and 6-min walk distance (6MWD). Concurrent validity, internal consistency, ceiling and floor effects, and responsiveness were assessed, followed by estimation of the MID by anchor-based (linear regression) and distribution-based methods (standard error of measurement). RESULTS: The UCSDSOBQ had a high level of internal consistency (Cronbach's alpha = 0.97), no obvious floor or ceiling effect, strong correlations with SGRQ, EQ-5D-5L, and EQ-VAS (|r| > 0.5), and moderate correlations with FVC%, DLCO%, and 6MWD (0.3 < |r| < 0.5). The MID estimate for UCSDSOBQ was 5 points (1-8) for the anchor-based method, and 4.5 points for the distribution-based method. CONCLUSION: This study demonstrates the validity of UCSDSOBQ in a large and heterogeneous population of patients with fibrotic ILD, and provides a robust MID estimate of 5-8 points.

Using a distribution-based approach and systematic review methods to derive minimum clinically important differences.

BACKGROUND: Clinical interpretation of changes measured on a scale is dependent on knowing the minimum clinically important difference (MCID) for that scale: the threshold above which clinicians, patients, and researchers perceive an outcome difference. Until now, approaches to determining MCIDs were based upon individual studies or surveys of experts. However, the comparison of meta-analytic treatment effects to a MCID derived from a distribution of standard deviations (SDs) associated with all trial-specific outcomes in a meta-analysis could improve our clinical understanding of meta-analytic treatment effects. METHODS: We approximated MCIDs using a distribution-based approach that pooled SDs associated with baseline mean or mean change values for two scales (i.e. Mini-Mental State Exam [MMSE] and Alzheimer Disease Assessment Scale - Cognitive Subscale [ADAS-Cog]), as reported in parallel randomized trials (RCTs) that were included in a systematic review of cognitive enhancing medications for dementia (i.e. cholinesterase inhibitors and memantine). We excluded RCTs that did not report baseline or mean change SD values. We derived MCIDs at 0.4 and 0.5 SDs of the pooled SD and compared our derived MCIDs to previously published MCIDs for the MMSE and ADAS-Cog. RESULTS: We showed that MCIDs derived from a distribution-based approach approximated published MCIDs for the MMSE and ADAS-Cog. For the MMSE (51 RCTs, 12,449 patients), we derived a MCID of 1.6 at 0.4 SDs and 2 at 0.5 SDs using baseline SDs and we derived a MCID of 1.4 at 0.4 SDs and 1.8 at 0.5 SDs using mean change SDs. For the ADAS-Cog (37 RCTs, 10,006 patients), we derived a MCID of 4 at 0.4 SDs and 5 at 0.5 SDs using baseline SDs and we derived a MCID of 2.6 at 0.4 SDs and 3.2 at 0.5 SDs using mean change SDs. CONCLUSION: A distribution-based approach using data included in a systematic review approximated known MCIDs. Our approach performed better when we derived MCIDs from baseline as opposed to mean change SDs. This approach could facilitate clinical interpretation of outcome measures reported in RCTs and systematic reviews of interventions. Future research should focus on the generalizability of this method to other clinical scenarios.

The minimum clinically important difference on the sleep disorders inventory for people with dementia.

OBJECTIVES: Sleep disturbances in dementia causes distress to people with dementia and their family carers and are associated with care home admission. The Sleep Disorders Inventory (SDI) is a validated questionnaire of sleep disturbances in dementia often used to measure treatment effectiveness, but the minimum clinically important difference (MCID) is unknown. METHODS: We triangulated three investigative methods to determine the MCID of the SDI. Using data on SDI from a randomised controlled trial (RCT) with 62 participants in an intervention for sleep disorders in dementia, we (1) calculated distribution-based values where MCID = 0.33 of a SD (SD) (2) an anchor based approach using quality of life (measured using DEMQOL-Proxy) as an anchor. We also employed a Delphi consensus process asking 12 clinicians, sleep researchers and family carers to rate which changes on vignettes were equivalent to a MCID. RESULTS: We found that 0.33 SD in the SDI = 4.86. Reduction in SDI total score was not significantly correlated with improvement in DEMQOL-Proxy (Pearson's correlation = -0.01; P = 0.96) score. The Delphi consensus required two rounds to reach a consensus and concluded that changes equivalent to three points on the SDI equated to the MCID. CONCLUSIONS: Taking into account both the distribution-based values and the Delphi process we used a whole number at the midpoint and judged the minimum clinically important difference MCID to be equal to four points. We note the clinicians and carers opinions from the Delphi process determined the MCID to be lower at three points.

Validity of the Japanese Core Outcome Measures Index (COMI)-Back for thoracic and lumbar spine surgery: a prospective cohort study.

PURPOSE: To investigate the psychometric properties of the Japanese version of the Core Outcome Measures Index-Back (COMI-Back), only recently published according to the established linguistic and cultural conversion guidelines, in patients undergoing spine surgery. METHODS: We recruited 145 patients who underwent thoracic or lumbar spine surgery in one of the five specific tertiary care institutions. They were asked to complete a booklet questionnaire (the COMI-Back, the Numerical Rating Scale for pain, the Short Form-12, Euro-QOL-5 dimensions, and Oswestry Disability Index) at baseline and 12 months postoperatively to investigate floor/ceiling effect, construct validity, and postoperative responsiveness. The patients were also asked to answer an anchor question (Global Treatment Outcome) to analyze the minimum clinically important difference (MCID) by receiver operating characteristics curves. Of the 145 patients, 112 completed the study. Another group of 59 volunteers with chronic symptoms completed the questionnaire twice within a 7-14-day interval for the test-retest reproducibility. RESULTS: The COMI summary score displayed no notable floor or ceiling effects. Except for symptom-specific well-being, the individual COMI domains and the COMI summary score correlated as expected with the scores of the chosen reference measures (ρ = 0.4-0.8). A similar trend was observed between the pre-/postoperative changes in the COMI score and those in the reference measures. The MCID for the COMI summary score was 2.5. The intraclass correlation coefficient and minimum detectable change (MDC95%) were 0.93 and 1.26, respectively. CONCLUSION: The Japanese COMI-Back was a reliable and responsive questionnaire in our Japanese patients undergoing thoracic/lumbar spine surgery. These slides can be retrieved under Electronic Supplementary Material.

The minimum clinically important difference: which direction to take.

Over the past decades in modern medicine, there has been a shift from statistical significance to clinical relevance when it comes to interpreting results from clinical trials. A concept that is increasingly being used as a surrogate for clinical relevance and effect size calculation is the minimum clinically important difference (MCID). In this paper, an overview is presented of the most important aspects of the MCID concept used in research trials and a discussion of what this means for the neurological patient in clinical trials and daily practice is given. Is the MCID the best outcome measure cut-off to be implemented?

Minimum clinically important difference in outcome scores among patients undergoing cervical laminoplasty.

PURPOSE: Minimum clinically important difference (MCID) represents the smallest change in an outcome measure recognized as clinically meaningful to a patient and is one of the most important psychometric parameters for assessing the postoperative results of spinal surgery. The purpose of the present study was to elucidate MCIDs for four common outcome measures used for degenerative cervical myelopathy in the context of patients undergoing laminoplasty. METHODS: We retrospectively reviewed a consecutive series of cervical laminoplasties in a single academic institution. Pre- and postoperative Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), Short Form-36 (SF-36), Neck Disability Index (NDI), and EuroQOL (EQ-5D) scores were obtained. Patients were also asked to answer the anchor question regarding satisfaction with treatment, and the anchor-based method was used to determine cut-off values for MCIDs. RESULTS: A total of 101 patients were included in the analysis. All outcome scores showed significant improvement postoperatively, with the exception of JOACMEQ bladder function score and SF-36 mental component summary score. Most patients (66%) were at least "somewhat satisfied" with treatment results. Receiver operating characteristic curve analyses revealed MCIDs of 2.5 for JOACEMQ cervical spine function, 13.0 for upper extremity function, 9.35 for lower extremity function, 9.5 for QOL, 3.9 for SF-36 physical component summary score, 4.2 for NDI, and 0.0485 for EQ-5D. CONCLUSION: The MCIDs of four outcome measures were determined for patients undergoing cervical laminoplasty. These slides can be retrieved under Electronic Supplementary Material.

Establishing the minimum clinically important difference for the Genetic Counseling Outcome Scale (GCOS-24).

To establish the smallest change in genetic counseling outcome that is meaningful for patients, the aim of this study was to establish the Minimum Clinically Important Difference (MCID) for the Genetic Counseling Outcome Scale (GCOS-24). GCOS-24 is a patient-reported outcome measure for clinical genetics services. Secondary aims included understanding what patients deem important for reaching this score. Participants were 74 new patients recruited from the All Wales Medical Genetics Service, between April 2016 and December 2016. An anchor-based, global transition question methodology was used to identify the MCID, by asking participants how much meaningful change they experienced following their genetics appointment, and comparing this with GCOS-24 change scores. This ensured that the established score was clinically meaningful to patients. Comments from a free text response box were analyzed using qualitative thematic analysis. The mean score of the group who felt "a little better" was determined to be the MCID. The MCID was established to be a GCOS-24 score increase of 10.3 points after a clinical genetics appointment. This score was significantly different from the group "neutral" (0.64 points), using an independent samples t test. Themes identified as important for reaching the MCID included "future and family". These findings contribute to interpretability of GCOS-24 and provide some useful insights for genetic counseling service development.

Machine learning-based preoperative predictive analytics for lumbar spinal stenosis.

OBJECTIVEPatient-reported outcome measures (PROMs) following decompression surgery for lumbar spinal stenosis (LSS) demonstrate considerable heterogeneity. Individualized prediction tools can provide valuable insights for shared decision-making. The authors aim to evaluate the feasibility of predicting short- and long-term PROMs, reoperations, and perioperative parameters by machine learning (ML) methods.METHODSData were derived from a prospective registry. All patients had undergone single- or multilevel mini-open facet-sparing decompression for LSS. The prediction models were trained using various ML-based algorithms to predict the endpoints of interest. Models were selected by area under the receiver operating characteristic curve (AUC). The endpoints were dichotomized by minimum clinically important difference (MCID) and included 6-week and 12-month numeric rating scales for back pain (NRS-BP) and leg pain (NRS-LP) severity and the Oswestry Disability Index (ODI), as well as prolonged surgery (> 45 minutes), extended length of hospital stay (> 28 hours), and reoperations.RESULTSA total of 635 patients were included. The average age was 62 ± 10 years, and 333 patients (52%) were male. At 6 weeks, MCID was seen in 63%, 76%, and 61% of patients for ODI, NRS-LP, and NRS-BP, respectively. At internal validation, the models predicted MCID in these variables with accuracies of 69%, 76%, and 85%, and with AUCs of 0.75, 0.79, and 0.92. At 12 months, 66%, 63%, and 51% of patients reported MCID; the observed accuracies were 62%, 74%, and 66%, with AUCs of 0.68, 0.72, and 0.79. Reoperations occurred in 60 patients (9.5%), of which 27 (4.3%) occurred at the index level. Overall and index-level reoperations were predicted with 69% and 63% accuracy, respectively, and with AUCs of 0.66 and 0.61. In 15%, a length of surgery greater than 45 minutes was observed and predicted with 78% accuracy and AUC of 0.54. Only 15% of patients were admitted to the hospital for longer than 28 hours. The developed ML-based model enabled prediction of extended hospital stay with an accuracy of 77% and AUC of 0.58.CONCLUSIONSPreoperative prediction of a range of clinically relevant endpoints in decompression surgery for LSS using ML is feasible, and may enable enhanced informed patient consent and personalized shared decision-making. Access to individualized preoperative predictive analytics for outcome and treatment risks may represent a further step in the evolution of surgical care for patients with LSS.

Objective functional assessment using the "Timed Up and Go" test in patients with lumbar spinal stenosis.

OBJECTIVEPatient-reported outcome measures (PROMs) are standard of care for the assessment of functional impairment. Subjective outcome measures are increasingly complemented by objective ones, such as the "Timed Up and Go" (TUG) test. Currently, only a few studies report pre- and postoperative TUG test assessments in patients with lumbar spinal stenosis (LSS).METHODSA prospective two-center database was reviewed to identify patients with LSS who underwent lumbar decompression with or without fusion. The subjective functional status was estimated using PROMs for pain (visual analog scale [VAS]), disability (Roland-Morris Disability Index [RMDI] and Oswestry Disability Index [ODI]), and health-related quality of life (HRQoL; 12-Item Short-Form Physical Component Summary [SF-12 PCS] and the EQ-5D) preoperatively, as well as on postoperative day 3 (D3) and week 6 (W6). Objective functional impairment (OFI) was measured using age- and sex-standardized TUG test results.RESULTSSixty-four patients (n = 32 [50%] male, mean age 66.8 ± 11.7 years) were included. Preoperatively, they reported a mean VAS back pain score of 4.1 ± 2.7, VAS leg pain score of 5.4 ± 2.7, RMDI of 10.4 ± 5.3, ODI of 41.9 ± 16.2, SF-12 PCS score of 32.7 ± 8.3, and an EQ-5D index of 0.517 ± 0.226. The preoperative rates of severe, moderate, and mild OFI were 4.7% (n = 3), 12.5% (n = 8), and 7.8% (n = 5), respectively, and the mean OFI T-score was 116.3 ± 23.7. At W6, 60 (93.8%) of 64 patients had a TUG test result within the normal population range (no OFI); 3 patients (4.7%) had mild and 1 patient (1.6%) severe OFI. The mean W6 OFI T-score was significantly decreased (103.1 ± 13.6; p < 0.001). Correspondingly, the PROMs showed a decrease in subjective VAS back pain (1.6 ± 1.7, p < 0.001) and leg pain (1.0 ± 1.8, p < 0.001) scores, disability (RMDI 5.3 ± 4.7, p < 0.001; ODI 21.3 ± 16.1, p < 0.001), and increase in HRQoL (SF-12 PCS 40.1 ± 8.3, p < 0.001; EQ-5D 0.737 ± 0.192, p < 0.001) at W6. The W6 responder status (clinically meaningful improvement) ranged between 81.3% (VAS leg pain) and 29.7% (EQ-5D index) of patients.CONCLUSIONSThe TUG test is a quick and easily applicable tool that reliably measures OFI in patients with LSS. Objective tests incorporating longer walking time should be considered if OFI is suspected but fails to be proven by the TUG test, taking into account that neurogenic claudication may not clinically manifest during the brief TUG examination. Objective tests do not replace the subjective PROM-based assessment, but add valuable information to a comprehensive patient evaluation.