Multiple patient-reported outcome measures (PROMs) have been used to assess shoulder function, but it is unknown which are the most effective. The purpose of this study was to report the multiple PROMs used after rotator cuff repair (RCR) and to compare the responsiveness between them. It was hypothesized that the Western Ontario Rotator Cuff PROM would be the most responsive and commonly used in patients undergoing RCR. Meta-analysis; Level of evidence, 4. A systematic review was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and PRISMA-Searching extension guidelines via PubMed/MEDLINE, Embase (Elsevier), and Web of Science (Clarivate). Patient and study characteristics were extracted. From the studies that met inclusion criteria for responsiveness analysis (≥2 PROMs reported, 1-year minimum follow-up, and pre- and postoperative PROM means and standard deviations reported), the authors compared the responsiveness between PROM instruments using effect size and relative efficiency (RE) if a PROM could be compared with another in ≥10 articles. A total of 252 studies met inclusion criteria (32,072 patients; mean age, 59.6 years; mean body mass index, 28.7; mean follow-up time, 27.8 months). Range of motion was reported in 131 (52%) studies and imaging findings were reported in 123 (49%) studies. There were 67 PROM instruments identified; the most commonly used were the American Shoulder and Elbow Surgeon (ASES) (n = 183; 73%), Visual Analog Scale (VAS) (n = 163; 65%), and Constant (n = 118; 47%) scores. The 3 PROMs with the highest effect sizes were the University of California, Los Angeles (UCLA) (2.51), Western Ontario Rotator Cuff (2.42), and ASES (2.00) scores. Overall, UCLA and ASES scores were the most responsive PROMs. The ASES PROM was more responsive than the VAS (RE, 1.70), Constant (RE, 2.76), Simple Shoulder Test (RE, 1.67), and Single Assessment Numeric Evaluation (RE, 2.14) scores. The UCLA PROM was more responsive than the ASES (RE, 1.03), VAS (RE, 3.66), Constant (RE, 1.72), and Simple Shoulder Test (RE, 1.66) scores. ASES and UCLA scores were the most responsive PROMs after RCR. The authors recommend widespread adoption of ASES and UCLA scores for clinical and research standardization; however, the UCLA PROM requires in-person range of motion and strength testing, which is a practical limitation and barrier to long-term follow-up.