Meniscal Tear and Osteathritis

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Corey Black
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1 Surgery versus Physical Therapy for a Meniscal Tear and Osteathritis To assess the efficacy of arthroscopic partial meniscectomy as compared with a standardized physical-therapy regime. Group 1: Inger Ahlstrand, Kjersti Claesson, Hanna Israelsson, Maria Sarberg, Karolina Kristenson, Lina De Geer

2 Design Multicenter RCT Participants: symptomatic patients 45 years or older with a meniscal tear and mild to moderate osteoarthritis Surgery OR standardized Physical Therapy program

3 Outcomes Primary outcome at 6 months WOMAC, physical-function score (changes from baseline WOMAC) Secundary outcomes KOOS, pain score SF-36, physical-activity score Clinical improvement ( 8 points) on WOMAC physical-function score The aim was to assess the efficacy of Surgery (arthroscopic partial meniscectomy ) versus Physical Therapy (standardized physical-therapy regime)

4 Intention to treat (ITT) modified intention to treat (mitt) ITT: Analyses based on the initial treatment assignment and not the treatment eventually received. All participants analyzed, no exceptions mitt: Analyses based on initial treatment assignment, but some participants may be excluded Individuals may be excluded due to problems with missing data or adherence to protocol Per-protocol Only individuals that completed the trial according to the assigned group are analysed

5 Statistical analysis Primary analysis - ANCOVA Dependent variable changes in WOMAC from baseline Independent variable Treatment Covariate Study site Secondary analysis ANCOVA and Logistic Regression Dependent variable for ANCOVA KOOS pain scores SF 36 physical activity scores

6 ANCOVA Analysis of Covariance ANOVA Compare the mean of a numerical outcome variable in between groups How much of the overall variation in outcome is attributed to the difference in treatment/exposure Instead of t-test for every combination, one single global test The variance within each group should be equal ANCOVA Examine difference between groups adjusted for the effect of covariates Covariate should be continuous

7 Regression Analyses Linear regression: Dependent: numerical Independent: one or several numerical and/or categorical variables Logistic regression: Dependent: categorical (clinical improvement yes/no) Independent: one or several numerical and/or categorical variables (treatment; study site)

8 Regression Analyses Linear regression: (dependent: numerical) y = a + b1x1 + b2x2 starting point variable 1 variable 2 slope of variable 1 slope of variable 2 Logistic regression: (dependent: categorical) logit y = a + b1x1 + b2x2 Odds ratios!

9 Logistic Regression Normally used in: Incidence of disease in longitudinal studies Binary outcome in cross-sectional studies Unmatched case-control studies Matched case-control studies (conditional) Categorical outcome with more than two outcomes (multinominal or ordinal) Categorical dependent - consider logistic regression!!

10 Results Primary outcome: Was there a difference in mean improvement in the WOMAC score between the groups after six months? (ANCOVA adjusted for study site, mitt) No difference!

11 Scores on the WOMAC physical-funcion score and KOOS pain scale over the 12-months follow-up period (ANCOVA, mitt)

12 WOMAC scores according to crossover status (ANCOVA, mitt)

13 Secondary outcome: Was there difference in clinical improvment (increase 8 points on the WOMAC scale) between the groups after six months? p=0,001 Logistic regression Per protocol analyse (persons who crossed over from PT to surgery excluded) % Surgery PT

14 Discussion Statistical considerations Variables Outcome variables Non-continuous scale used as continuous. Logistic regression instead of ANCOVA in primary analyses? Methods ANCOVA To adjust for study location otherwise plain T-test! Study location (the covariate) is categorical in fact a two way ANOVA? Logistic regression Used in secondary but not for primary outcome analysis. Covariates Pre-specified covariates not included in multivariable analyses No difference between groups? Not specified. What would have happened if included?

15 Discussion Methodological considerations Pilot study Used to calculate sample size, but still too small Design Intention to treat Per protocol Cross-over 30% from one arm to the other Impact of results from those who crossed over?

16 Conclusion: No matter what intended or recieved treatment, all patients got better in the end!

1.0 Abstract. Title: Real Life Evaluation of Rheumatoid Arthritis in Canadians taking HUMIRA. Keywords. Rationale and Background:

1.0 Abstract. Title: Real Life Evaluation of Rheumatoid Arthritis in Canadians taking HUMIRA. Keywords. Rationale and Background: 1.0 Abstract Title: Real Life Evaluation of Rheumatoid Arthritis in Canadians taking HUMIRA Keywords Rationale and Background: This abbreviated clinical study report is based on a clinical surveillance