Poster Presentation 50th International Society for the Study of the Lumbar Spine Annual Meeting 2024

Introduction. Net Promoter Score (NPS) is a pivotal customer loyalty index, which summarizes scores on a scale zero to ten when companies ask customers how likely they are to recommend the company to a friend or colleague. Widely adopted in various industries, NPS is recognized for its tighter correlation with business performance compared to traditional customer satisfaction surveys. However, there is limited literature on NPS within healthcare institutions, particularly in the context of lumbar and spine surgeries. This study presents the first-ever report on NPS for a range of lumbar operations.

Methods. Our institutions have surveyed patient satisfaction (PS) on a ten-point scale and NPS and reasons for scoring both scales three months after operation. 3372 valid responses were acquired from patients who underwent these questionnaires from June 2021, when we started the NPS survey, to March 2023 at Iwai Orthopaedic Hospital and Inanami Spine and Joint Hospital. Sorted by the kind of lumbar operations, seven surgeries contained more than 45 cases as follows: MED (microendoscopic discectomy), MEL (microendoscopic laminectomy), ME-PLIF (microendoscopy assisted-posterior lumbar interbody fusion), OLIF (oblique lateral interbody fusion), XLIF (extreme lateral interbody fusion), FELD (full-endoscopic lumbar discectomy), DPEL (dynamic percutaneous endoscopic laminectomy). We assessed these surgeries about NPS and PS.

Results. The overall NPS was 48.1, with an average PS score (PSS) of 7.82 across all cases. The NPS, average PSS, and case numbers for each surgery were as follows: MED (856 cases, NPS 54.7, PSS 8.08), MEL (1,121 cases, NPS 42.5, PSS 7.77), ME-PLIF (217 cases, NPS 42.4, PSS 7.63), OLIF (98 cases, NPS 54.1, PSS 7.56), XLIF (72 cases, NPS 47.2, PSS 7.96), FELD (393 cases, NPS 56.0, PSS 8.06), and DPEL (82 cases, NPS 26.8, PSS 6.98). The correlation coefficient (R) and coefficient of determination (R²) between NPS and PSS were 0.838 and 0.702, respectively.

Discussion. FED and MED exhibited the highest NPS and PSS, suggesting endoscopic surgeries for lumbar discectomy tend to elicit positive referral sentiments and satisfaction aligning with the beliefs of most spine surgeons. Contrary to expectations, fusion surgeries resulted in higher NPS scores, and full-endoscopic decompression surgeries, considered the least invasive, did not consistently yield higher scores. Finally, high R² between NPS and PSS underscores a strong correlation between them. However, as the reasons of scoring PS and NPS were analyzed, while PS scores are influenced by symptom development, NPS questions assess facility and hospitalization systems, offering opportunities for enhancing healthcare quality. Therefore, NPS is one of the useful tools to enhance the quality, and efforts to improve NPS will benefit not only our hospitals but also contribute to the overall patient experience.