Background. Patient-Reported Outcome Measures (PROMs) are an extensively used tool to assess and improve the quality of healthcare services. PROMs are affected by individual characteristics in patients undergoing hip arthroplasty (HA). The aim of this study is to identify distinct groups of patients with unique score-trajectories using the Latent Class Growth Analysis (LCGA) technique and to determine patientsâ features associated with these groups.Methods. We conducted a prospective, cohort study analyzing PROMs questionnaires (Euro Quality 5 Dimensions 3L, EQ-5D-3L, Euro-Quality-Visual-Analytic-Score, EQ-VAS, Hip disability and Osteoarthritis Outcome Score, HOOS-PS) administered to patients undergoing elective HA at successive time points. For each score, LCGA was carried out to identify subgroups of patients assessed pre-operatively, and at 6 and 12 months after HA. Multinomial logistic regression was used to identify the demographic and clinical characteristics associated with the latent trajectories.Results. We identified three distinct trajectories for each PROM score. These trajectories indicated high response heterogeneity to the HA among the patients (n=991): one trajectory showing an improvement at 6 months followed by a plateau, a second trajectory showing a lower starting level followed by a consistent improvement, and a third trajectory showing a modest improvement at 6 months followed by a modest decline at 12 months. Patientâs gender, ASA score â„3, obesity and the main diagnosis were significantly associated with different PROMs trajectories.Conclusions. These findings underline the importance of patient-centered care, supporting the usefulness of integrating PROMs data alongside routinely collected healthcare records for guiding clinical care and maximizing patient outcomes. Trial registration number: Protocol version (1.0) and trial registration data are available on the platform www.clinicaltrial.gov with the identifier NCT03790267, posted on December 31, 2018.