Early outcomes after first reverse total shoulder arthroplasty better prognosticate contralateral success compared with early outcomes after anatomic total shoulder arthroplasty

BACKGROUND

The ideal timing between bilateral total shoulder arthroplasty (TSA) is unclear. The purpose of this study is to determine whether early outcomes after first TSA can be used to predict clinical outcomes after TSA of the contralateral shoulder and to evaluate the ideal time after TSA to perform the contralateral shoulder.

METHODS

A single-institution prospectively collected shoulder arthroplasty database was reviewed. Patients who underwent bilateral primary anatomic or reverse TSA (aTSA + rTSA) without an indication of fracture, tumor, or infection were identified. Included patients had minimum 2-year follow-up on their second TSA and postoperative follow-up after their first TSA at 3 months, 6 months, 1 year, or 2 years. Our primary outcome was whether outcome scores and motion at 3-month, 6-month, 1-year, and 2-year follow-up after first TSA predicted clinical success after second TSA at final follow-up, defined as achieving the patient acceptable symptomatic state (PASS = the highest level of symptoms beyond which patients consider themselves well). Outcomes included the American Shoulder and Elbow Surgeons and Constant scores, abduction, forward elevation, and external/internal-rotation. Multivariable logistic regression determined whether postoperative outcomes after first TSA were predictive of achieving the PASS after second TSA independent of age, sex, and body mass index. Receiver operating characteristic analysis determined cutoffs of postoperative outcomes after first TSA at each time point that best predicted achieving the prosthesis-specific PASS after second TSA.

RESULTS

One hundred thirty-four patients were included in the final analysis (110 aTSA and 158 rTSA). Range of motion and outcome scores at late (1- or 2-year) follow-up after first aTSA were more predictive of achieving the second TSA PASS compared with early (3- or 6-month) outcomes. In contrast, outcomes after early and late follow-up after first rTSA were similarly predictive of achieving the second TSA PASS. Specifically, the Constant score threshold at 2 years after first aTSA (79.4; area under the curve [AUC] = 0.804) better differentiated achieving the second TSA PASS vs. the 6-month threshold (72.0; AUC = 0.600). In contrast, the Constant score threshold at 2 years after first rTSA (76.4; AUC = 0.703) was similarly discriminant of achieving the second TSA PASS compared with the 6-month threshold (65.8; AUC = 0.711).

CONCLUSIONS

Patients with good outcomes after first rTSA can be counseled on contralateral TSA as early as 3 months postoperatively with confidence of a similar result on the contralateral side. In contrast, success after first aTSA does not reliably predict contralateral success until ≥1 year.

Minimum Clinically Important Difference (MCID) and Patient Acceptable Symptomatic State (PASS) Applied to the SF-36 in Patients Who Underwent Arthroscopic Rotator Cuff Repair

The 36-Item Short-Form Health Survey questionnaire (SF-36) is a reliable tool to assess the health-related quality of life of patients. If a mean difference between pre-operative evaluation and final follow-up is found to be statistically significant, then the change in score is not random. However, a statistically significant mean change may not correspond to a clinical amelioration for the patient or mean that the patient's state of health is to be considered acceptable. For this reason, interest in the concepts of minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) has grown within recent years. The goal of the present work of research was to determine the MCID and PASS values for the SF-36 in patients who received rotator cuff repair (RCR). Forty-six patients (18 women and 28 men, mean age 58.5 ± 12.9) previously diagnosed with rotator cuff disease were enrolled. All of these patients underwent RCR. They were evaluated pre-operatively and six months after the surgical intervention as a final follow-up. The SF-36 questionnaire was assessed at each evaluation. The MCID cut-offs of the total, physical, and mental dimensions of the SF-36 for patients who underwent RCR were 23.1, 32.5, and 18.1, respectively. A 23.1 improvement in the SF-36 score at six months following RCR can be correlated with patients having reached a clinically significant improvement in health status. If 81.9 or more is attained in the SF-36 score after surgical repair, the symptom state can be judged as satisfactory by the majority of patients.

Threshold Values for Success After Hip Arthroscopy Using the Patient-Reported Outcomes Measurement Information System Assessment: Determining the Minimum Clinically Important Difference and Patient Acceptable Symptomatic State

BACKGROUND

Threshold values for patient-reported outcome measures, such as the minimum clinically important difference (MCID) and patient acceptable symptomatic state (PASS), are important for relating postoperative outcomes to meaningful functional improvement.

PURPOSE

To determine the PASS and MCID after hip arthroscopy for femoroacetabular impingement using the Patient-Reported Outcomes Measurement Information System (PROMIS) questionnaire.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 3.

METHODS

A consecutive series of patients undergoing primary hip arthroscopy for femoroacetabular impingement were administered preoperative and minimum 1-year postoperative PROMIS surveys focusing on physical function (PF) and pain interference (PI). External anchor questions for the MCID and PASS were given with the postoperative PROMIS survey. Receiver operator curves were constructed to determine the threshold values for the MCID and PASS. Curves were generated for the study population as well as separate cohorts segregated by median baseline PF or PI scores and preoperative athletic participation. A multivariate post hoc analysis was then constructed to evaluate factors associated with achieving the PASS or MCID.

RESULTS

There were 113 patients (35% male; mean ± SD age, 32.8 ± 12.5 years; body mass index, 25.8 ± 4.8 kg/m²), with 60 (53%) reporting preoperative athletic participation. Survey time averaged 77.5 ± 49.2 seconds. Anchor-based MCID values were 5.1 and 10.9 for the PF and PI domains, respectively. PASS thresholds were 51.8 and 51.9 for the PF and PI, respectively. PASS values were not affected by baseline scores, but athletic patients had a higher PASS threshold than did those not participating in a sport (53.1 vs 44.7). MCID values were affected by preoperative baseline scores but were largely independent of sports participation. A post hoc analysis found that 94 (83%) patients attained the MCID PF while 66 (58%) attained the PASS PF. A multivariate nominal logistic regression found that younger patients (P = .01) and athletic patients (P = .003) were more likely to attain the PASS.

CONCLUSION

The PROMIS survey is an efficient metric to evaluate preoperative disability and postoperative function after primary hip arthroscopy for femoroacetabular impingement. The MCID and PASS provide surgeons with threshold values to help determine PROMIS scores that are clinically meaningful to patients, and they can assist with therapeutic decision making as well as expectation setting.

Minimal Clinically Important Difference, Substantial Clinical Benefit, and Patient Acceptable Symptomatic State After Arthroscopic Rotator Cuff Repair

BACKGROUND

Minimal clinically important difference (MCID), substantial clinical benefit (SCB), and patient acceptable symptomatic state (PASS) are emerging criteria for patient-based treatment assessments. However, few studies have investigated these measures after rotator cuff repair.

PURPOSE

(1) To determine MCID, SCB, and PASS values for pain visual analog scale (pVAS), Single Assessment Numeric Evaluation (SANE), American Shoulder and Elbow Surgeons (ASES) score, and University of California, Los Angeles (UCLA) score after arthroscopic rotator cuff repair. (2) To determine factors for achieving the MCID, SCB, and PASS.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

We analyzed prospectively collected data from a rotator cuff surgery registry between March 2018 and February 2019. Eighty-two patients were included, and anchor questions for deriving MCID, SCB, and PASS values were applied at 1-year follow-up after the surgery. The MCID and SCB for the pVAS, ASES, SANE, and UCLA scores were then derived via 2 methods: a sensitivity- and specificity-based approach, which was used alone to derive PASS values, and a between-patients approach. Additionally, univariable and multivariable logistic regression analyses were performed to determine factors for achieving the MCID, SCB, and PASS.

RESULTS

All 4 scores showed acceptable areas under the curve. MCID, SCB, and PASS values for the pVAS were 1.5, 2.5, and 1.7; for ASES scores, 21.0, 26.0, and 78.0; for SANE, 13.0, 20.0, and 71.0; and for UCLA scores, 6.0, 8.0, and 23.0, respectively. Poor preoperative scores demonstrated significantly higher odds ratios (ORs) for achieving the MCID and SCB and lower ORs for achieving the PASS. Retear, large to massive tear, and older age showed lower ORs for achieving the MCID or SCB. For PASS items, male sex and biceps tenodesis had higher ORs, and older age had lower ORs. MCID, SCB, and PASS values per the sensitivity- and specificity-based approach were applied in factor analyses.

CONCLUSION

Reliable MCID, SCB, and PASS values were obtained from patient evaluations 1 year after arthroscopic rotator cuff surgery. Poor preoperative score (MCID and SCB), male sex, and biceps tenodesis showed higher ORs, whereas poor preoperative score (PASS), retear, large to massive tear, and older age demonstrated lower ORs.

Determining the Patient Acceptable Symptomatic State for Patients Undergoing Arthroscopic Partial Meniscectomy in the Knee

BACKGROUND

Arthroscopic partial meniscectomy is one of the most common procedures in orthopaedic surgery. The patient acceptable symptomatic state (PASS), which defines a level of symptoms above which patients consider themselves well, remains to be well-defined in this population.

PURPOSE

Using an anchor-based approach, our goal was to determine the 1-year PASS for the Knee injury and Osteoarthritis Outcome Score (KOOS), the International Knee Documentation Committee (IKDC) Subjective Knee Form, the Western Ontario Meniscal Evaluation Tool (WOMET), and the Marx Activity Scale (MAS) in patients who were treated with partial knee meniscectomy.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A consecutive series of patients with knee meniscal tears and a Kellgren-Lawrence grade of 0 to 2 treated with arthroscopic partial meniscectomy were eligible. The KOOS (0-100), IKDC (0-100), WOMET (0-100), and MAS (0-16) were administered at baseline and 12 months postoperatively. An external anchor question at 1 year postoperatively was used to determine PASS values. A receiver operating characteristic curve (ROC) analysis was used to determine the PASS value at which patients considered their status to be satisfactory.

RESULTS

The study included 110 patients (mean ± SD age, 53.8 ± 12.0 years), 57.3% were male, and the follow-up rate was 82%. In total, 70% of patients had an Outerbridge arthroscopic grade of 2 or lower. Based on ROC analysis, the 1-year postoperative PASS values (sensitivity, specificity) were 64.3 (47.8, 100.0) for KOOS Symptoms, 81.6 (71.6, 100.0) for KOOS Pain, 82.4 (82.1, 86.4) for KOOS Function in Daily Living, 71.0 (62.7, 81.8) for KOOS Function in Sport and Recreation, 51.0 (83.6, 95.5) for KOOS Knee-Related Quality of Life, 56.2 (82.1, 100.0) for IKDC, 58.5 (79.1, 100.0) for WOMET, and 7.0 (44.8, 68.2) for MAS. Baseline scores did not affect the PASS threshold across the different instruments. However, patients with higher baseline scores were more likely to achieve the PASS for the KOOS Symptoms (odds ratio [OR], 2.808; P = .047), IKDC (OR, 4.735; P = .006), and WOMET (OR, 2.985; P = .036). Age, sex, and cartilage status were not significantly related to the odds of achieving the PASS for any of the patient-reported outcome measures.

CONCLUSION

These findings allow researchers and clinicians to determine whether partial meniscectomy is meaningful to patients at the individual level and will be helpful for responder analysis in future trials related to the treatment of meniscal abnormality.

Single Assessment Numeric Evaluation (SANE) is a reliable metric to measure clinically significant improvements following shoulder arthroplasty

BACKGROUND

Single Assessment Numeric Evaluation (SANE) offers a simple method of evaluating patients' sense of functional improvement after shoulder arthroplasty.

METHODS

Patients receiving total shoulder arthroplasties were retrospectively queried between 2014 and 2017. Patients completed questionnaires involving SANE, American Shoulder and Elbow Surgeons (ASES) score, and Constant scores at the 1-year interval. Minimal clinically important difference (MCID), substantial clinical benefit (SCB), and patient acceptable symptomatic state (PASS) were calculated using the anchor-based methodology.

RESULTS

A total of 207 patients with an average age of 66.7 ± 10.3 years and a body mass index of 31.5 ± 7.3 were available for analysis. The SANE score was the only score to have acceptable area under curve (AUC) (70.5%) for achieving MCID with a cutoff of 28.8. In terms of SCB, ASES (88%) and SANE (70.5%) had acceptable AUC with cutoffs of 20.7 and 50.2, respectively. All 3 scores had excellent AUC (>80%) for PASS with cutoffs of 81.9, 75.5, and 24.5 for ASES, SANE, and Constant scores, respectively. Normalized SANE scores were weakly correlated with ASES and Subjective Constant after normalizing for scale (R2 < 0.4). Achieving MCID by SANE was correlated with achieving MCID by Constant (P < .001). Achieving SCB and PASS by SANE was correlated with achieving SCB and PASS by ASES and Constant (ASES: P = .007, P < .001; Constant: P < .001, P < .001).

CONCLUSION

The present study establishes clinically significant outcomes for SANE. Achievement of clinically significant outcomes in SANE was correlated with achieving meaningful outcomes with legacy measures of ASES and Constant scores. SANE may be used as a simple and efficient measure of patient outcome after total shoulder arthroplasty.

Defining Minimal Clinically Important Difference and Patient Acceptable Symptom State After Isolated Endoscopic Gluteus Medius Repair

BACKGROUND

Endoscopic surgical repair has become a common procedure for treating patients with gluteus medius tears. However, meaningful clinical outcomes after the procedure have not been defined.

PURPOSE

To (1) define the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) in patients undergoing endoscopic gluteus medius repair and (2) determine correlations between preoperative patient characteristics and achievement of MCID/PASS.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A retrospective review was performed of prospectively collected data from all patients undergoing primary endoscopic repair of gluteus medius tears between January 2012 and February 2017 with a minimum 2-year follow-up. Patient data collected included patient characteristics, radiographic parameters, preoperative clinical function scores, and postoperative patient-reported outcomes (PROs). Paired t tests were used to compare the differences in 2-year PROs. The MCID and PASS for each PRO were calculated and Spearman coefficient analysis was used to identify correlations between MCID, PASS, and preoperative variables.

RESULTS

A total of 60 patients were included in the study. A majority of patients were female (91.7%), with an average age and body mass index of 57.9 ± 9.91 years and 27.6 ± 6.1, respectively. The MCIDs of the Activities of Daily Living (ADL) and Sport-Specific (SS) subscales of the Hip Outcome Score (HOS) and the modified Harris Hip Score (mHHS) were calculated to be 15.02, 14.53, and 14.13, respectively. The PASS scores of HOS-ADL, HOS-SS, and mHHS were calculated to be 81.32, 67.71, and 77.5, respectively. In addition, 76.7% of patients achieved either MCID or PASS postoperatively, with 77.8% and 69.0% reaching at least 1 threshold score for achieving MCID and PASS, respectively, and 48.3% achieving both MCID and PASS. Smoking had a negative and weak association with achieving PASS (r = -0.271; P = .039). No other patient characteristic variables were found to correlate with achieving MCID or PASS.

CONCLUSION

In patients undergoing endoscopic gluteus medius repair, our study defined MCID and PASS for HOS-ADL, HOS-SS, and mHHS outcome scores. A large percentage of patients (76.7%) achieved meaningful clinical outcomes at 2 years after surgery.

Prevalence and Clinical Implications of Chondral Injuries After Hip Arthroscopic Surgery for Femoroacetabular Impingement Syndrome

BACKGROUND

Studies on the effect of partial- and full-thickness chondral damage of the hip on outcomes and the ability to achieve meaningful clinical outcomes are limited.

PURPOSE

To determine the effect of full- and partial-thickness chondral injuries on 2-year outcomes in patients undergoing hip arthroscopic surgery for femoroacetabular impingement syndrome (FAIS) compared with patients without chondral damage, and to identify significant predictors of achieving the patient acceptable symptomatic state (PASS) and minimal clinically important difference (MCID).

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Data from consecutive patients with evidence of chondromalacia at the time of primary hip arthroscopic surgery with routine capsular closure for the treatment of FAIS by a single fellowship-trained surgeon between January 2012 and September 2016 were reviewed. Patients were divided into groups with partial-thickness (grade I-III) or full-thickness (grade IV) chondral defects and matched by age and body mass index (BMI) to patients without chondral injuries. Preoperative and postoperative outcomes were compared among the 3 groups, and a binary logistic regression analysis was utilized to identify significant predictors of achieving the MCID and PASS.

RESULTS

There were 634 patients included in the analysis, with a mean age of 34.5 ± 10.9 years and a mean BMI of 25.2 ± 4.7 kg/m². A total of 493 (77.8%) patients had no evidence of chondral damage, 92 (14.5%) patients had partial-thickness chondral defects, and 49 (7.7%) patients had full-thickness chondral defects. There were statistically significant differences in the Hip Outcome Score (HOS)-Activities of Daily Living, HOS-Sports Subscale, modified Harris Hip Score, pain, and satisfaction (P < .01) among the 3 groups. Patients with grade IV chondromalacia experienced the poorest outcomes and lowest percentage of achieving the PASS. Predictors for achieving any PASS threshold included preoperative alpha angle (odds ratio [OR], 0.96; P = .016), absence of preoperative limping (OR, 7.25; P = .002), absence of preoperative chronic pain (OR, 5.83; P = .019), primary hip arthroscopic surgery (OR, 0.17; P = .050), patients who self-identified as runners (OR, 2.27; P = .037), and Tönnis grade 0 (OR, 2.86; P = .032). Male sex (OR, 2.49; P = .015) was the only predictor of achieving any MCID threshold.

CONCLUSION

Patients with grade IV chondral defects experienced worse functional outcomes, lower satisfaction, and increased pain when compared with both patients without chondral damage or grade I-III chondromalacia at 2-year follow-up. Several predictors were associated with achieving clinically significant function in patients undergoing hip arthroscopic surgery for FAIS.

Establishing minimal clinically important difference, substantial clinical benefit, and patient acceptable symptomatic state after biceps tenodesis

BACKGROUND

The purposes of this study were to establish thresholds for improvement in patient-reported outcome scores that signify the minimal clinically important difference (MCID), substantial clinical benefit (SCB), and patient acceptable symptomatic state (PASS) after biceps tenodesis (BT) and to assess patient variables that are associated with these clinically important outcomes.

METHODS

A prospectively maintained institutional shoulder registry was queried for patients undergoing isolated BT between 2014 and 2017. Anchor-based and distribution-based approaches were used to calculate the MCID whereas an anchor-based method was used to calculate the SCB and PASS for the Constant-Murley score, Single Assessment Numerical Evaluation (SANE) score, and American Shoulder and Elbow Surgeons score.

RESULTS

A total of 123 patients who underwent isolated BT were included for analysis. The MCID, SCB, and PASS calculated for the American Shoulder and Elbow Surgeons score were 11.0, 16.8, and 59.6, respectively. For the Constant-Murley score, the calculated MCID and PASS were 3.8 and 19.5, respectively. The MCID, SCB, and PASS calculated for the SANE score were 3.5, 5.8, and 65.5, respectively. The following patient variables were significantly associated with decreased odds of achieving the MCID: workers' compensation status, male sex, and higher preoperative SANE score. Patients with a history of ipsilateral shoulder surgery had significantly reduced odds of achieving SCB. The only factor significantly associated with failing to reach the PASS was workers' compensation status.

CONCLUSION

This study established values for the MCID, SCB, and PASS after BT without concomitant rotator cuff repair. Workers' compensation status, previous shoulder surgery, male sex, and higher preoperative patient-reported outcome measure scores are associated with lower odds of achieving clinically significant improvement after BT.

Establishing Clinically Significant Outcomes After Meniscal Allograft Transplantation

Background:

Traditionally, the primary outcome in meniscal allograft transplantation (MAT) has been long-term survivorship; however, short-term clinically significant outcomes are necessary to fully evaluate patient improvement after surgery.

Purpose:

To (1) establish the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) with respect to patient-reported outcome measures (PROMs) and (2) evaluate preoperative and intraoperative variables correlated with achieving these threshold values.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

A prospectively maintained institutional registry was queried for all MATs performed between 1999 and 2017. The following PROM scores were collected: International Knee Documentation Committee (IKDC) score, Lysholm score, and Knee injury and Osteoarthritis Outcome Score (KOOS). Patients who completed preoperative and postoperative PROMs within a 1-month window were included to calculate the distribution-based MCID at this interval. An anchor question regarding satisfaction with surgery was asked at the same time point and was employed to determine the PASS using nonparametric receiver operating characteristic curve/area under the curve analysis. Multivariate regression analysis was performed to correlate patient demographics, medical history, and concomitant procedures to propensity in achieving the MCID and PASS.

Results:

A total of 98 patients who underwent MAT met the inclusion/exclusion criteria, of whom 10 underwent concomitant ligamentous procedures, 65 underwent concomitant cartilage procedures, and 7 underwent concomitant realignment procedures. The mean patient age was 29.4 ± 9.0 years, and the mean body mass index (BMI) was 26.8 ± 5.2 kg/m². The distribution-based MCID and PASS were determined for the Lysholm score (12.3 and 66.5) and IKDC (9.9 and 36.0) as well as the KOOS Pain (9.9 and N/A ), Symptoms (9.7 and 73.0), Activities of Daily Living (9.5 and N/A), Sport (13.3 and N/A), and Quality of Life (14.6 and 53.0) subscales, respectively. A preoperative Short Form Physical Component Summary (SF PCS) score greater than 32.0 was predictive of postoperative satisfaction. Patients with work-related claims had a reduced likelihood of achieving the MCID for the IKDC and the PASS for the KOOS Symptoms. An increased BMI was also associated with failing to achieve the PASS for the KOOS Quality of Life (QOL).

Conclusion:

This study established the MCID and PASS for the Lysholm score, IKDC, and KOOS in patients undergoing MAT. Workers’ compensation and higher BMI were associated with failing to achieve clinically significant values. Lower preoperative Lysholm, IKDC, and KOOS scores were predictive of achieving the MCID, while higher preoperative SF PCS scores were associated with achieving satisfaction after MAT.

The Patient Acceptable Symptomatic State for the Modified Harris Hip Score and Hip Outcome Score Among Patients Undergoing Surgical Treatment for Femoroacetabular Impingement

BACKGROUND

There is minimal information available on the threshold at which patients consider themselves to be well for patient-reported outcome measures used in patients treated with hip arthroscopy for femoroacetabular impingement (FAI).

PURPOSE

To determine the patient acceptable symptomatic state (PASS) for the modified Harris Hip Score (mHHS) and the Hip Outcome Score (HOS) in patients with FAI treated with arthroscopic hip surgery.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

A consecutive series of patients at a single institution with FAI who were treated with arthroscopic labral surgery, acetabular rim trimming, and femoral osteochondroplasty were eligible. The mHHS (score range, 0-100) and the HOS (score range, 0-100) were administered at baseline and at 12 months postoperatively. An external anchor question at 1 year postoperatively was utilized to determine PASS values: "Taking into account all the activities you have during your daily life, your level of pain, and also your functional impairment, do you consider that your current state is satisfactory?"

RESULTS

There were 130 patients (mean ± SD age, 35.6 ± 11.7 years), and 42.3% were male. Based on a receiver operator curve analysis, the PASS values-at which patients considered their status to be satisfactory-at 1 year after surgery were 74 (mHHS), 87 (HOS-activities of daily living subscale), and 75 (HOS-sports subscale). The PASS threshold was not affected by baseline scores across different instruments. However, patients with higher baseline scores were more likely to achieve the PASS (odds ratios: 3.36 [mHHS], 3.83 [HOS-activities of daily living], 3.38 [HOS-sports]). Age and sex were not significantly related to the odds of achieving the PASS for the mHHS or the HOS.

CONCLUSION

This is the first study to determine the PASS for 2 commonly used hip joint patient-reported outcome measures in patients undergoing surgery for FAI. The study findings can allow researchers to determine if interventions related to FAI are meaningful to patients at the individual level across various domains and will also be useful for responder analyses in future randomized trials related to hip arthroscopy and the treatment of FAI.

Minimal clinically important improvement and patient acceptable symptom state for subjective outcome measures in rheumatic disorders

The concepts of minimal clinically important improvement (MCII) and patient acceptable symptomatic state (PASS) could help in interpreting results of trials involving patient-reported outcomes by translating the response at the group level (change in mean scores) into more clinically meaningful information by addressing the patient level as "therapeutic success (yes/no)." The aims of the special interest group (SIG) at OMERACT 8 were to discuss specific issues concerning the MCII and PASS concepts, especially the wording of the external anchor questions used to determine the MCII and PASS estimates, and to move toward a consensus for the cutoff values to use as the MCII and PASS in the different outcome criteria. The purpose of this SIG at OMERACT 8 was to inform participants of the MCII and PASS concepts and to agree on MCII and PASS values for pain, patient global assessment, and functional impairment.