PMID- 37243547 OWN - NLM STAT- MEDLINE DCOM- 20230904 LR - 20230905 IS - 1547-5646 (Electronic) IS - 1547-5646 (Linking) VI - 39 IP - 3 DP - 2023 Sep 1 TI - Defining the minimal clinically important difference in smartphone-based mobility after spine surgery: correlation of survey questionnaire to mobility data. PG - 427-437 LID - 10.3171/2023.5.SPINE23336 [doi] AB - OBJECTIVE: Patient-reported outcome measures (PROMs) are the gold standard for assessing postoperative outcomes in spine surgery. However, PROMs are also limited by the inherent subjectivity of self-reported qualitative data. Recent literature has highlighted the utility of patient mobility data streamed from smartphone accelerometers as an objective measure of functional outcomes and complement to traditional PROMs. Still, for activity-based data to supplement existing PROMs, they must be validated against current metrics. In this study, the authors assessed the relationships and concordance between longitudinal smartphone-based mobility data and PROMs. METHODS: Patients receiving laminectomy (n = 21) or fusion (n = 10) between 2017 and 2022 were retrospectively included. Activity data (steps-per-day count) recorded in the Apple Health mobile application over a 2-year perioperative window were extracted and subsequently normalized to allow for intersubject comparison. PROMS, including the visual analog scale (VAS), Patient Reported Outcome Measurement Information System Pain Interference (PROMIS-PI), Oswestry Disability Index (ODI), and EQ-5D, collected at the preoperative and 6-week postoperative visits were retrospectively extracted from the electronic medical record. Correlations between PROMs and patient mobility were assessed and compared between patients who did and those who did not achieve the established minimal clinically important difference (MCID) for each measure. RESULTS: A total of 31 patients receiving laminectomy (n = 21) or fusion (n = 10) were included. Change between preoperative and 6-week postoperative VAS and PROMIS-PI scores demonstrated moderate (r = -0.46) and strong (r = -0.74) inverse correlations, respectively, with changes in normalized steps-per-day count. In cohorts of patients who achieved PROMIS-PI MCID postoperatively, indicating subjective improvement in pain, there was a 0.784 standard deviation increase in normalized steps per day, representing a 56.5% improvement (p = 0.027). Patients who did achieve the MCID of improvement in either PROMIS-PI or VAS after surgery were more likely to experience an earlier sustained improvement in physical activity commensurate to or greater than their preoperative baseline (p = 2.98 x 10-18) than non-MCID patients. CONCLUSIONS: This study demonstrates a strong correlation between changes in mobility data extracted from patient smartphones and changes in PROMs following spine surgery. Further elucidating this relationship will allow for more robust supplementation of existing spine outcome measure tools with analyzed objective activity data. FAU - Chauhan, Daksh AU - Chauhan D AD - 1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and. FAU - Ahmad, Hasan S AU - Ahmad HS AD - 1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and. FAU - Subtirelu, Robert AU - Subtirelu R AD - 1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and. FAU - Mannam, Sai AU - Mannam S AD - 1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and. FAU - Turlip, Ryan AU - Turlip R AD - 1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and. FAU - Bryan, Kevin AU - Bryan K AD - 1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and. FAU - Bathula, Shreya AU - Bathula S AD - 1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and. FAU - Ghenbot, Yohannes AU - Ghenbot Y AD - 1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and. FAU - Yang, Andrew I AU - Yang AI AD - 1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and. FAU - Wang, Michael Y AU - Wang MY AD - 2Department of Neurosurgery, Miller School of Medicine at the University of Miami, Florida. FAU - Basil, Gregory AU - Basil G AD - 2Department of Neurosurgery, Miller School of Medicine at the University of Miami, Florida. FAU - Ali, Zarina S AU - Ali ZS AD - 1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and. FAU - Yoon, Jang W AU - Yoon JW AD - 1Department of Neurosurgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania; and. LA - eng PT - Journal Article DEP - 20230526 PL - United States TA - J Neurosurg Spine JT - Journal of neurosurgery. Spine JID - 101223545 SB - IM MH - Humans MH - *Minimal Clinically Important Difference MH - *Smartphone MH - Retrospective Studies MH - Mobility Limitation MH - Patient Reported Outcome Measures MH - Surveys and Questionnaires MH - Pain MH - Treatment Outcome OTO - NOTNLM OT - PROMs OT - correlation testing OT - data science OT - objective outcomes OT - outcome research OT - patient-reported outcome measures OT - smartphones OT - visualization EDAT- 2023/05/27 19:12 MHDA- 2023/09/04 06:42 CRDT- 2023/05/27 07:23 PHST- 2023/03/27 00:00 [received] PHST- 2023/05/01 00:00 [accepted] PHST- 2023/09/04 06:42 [medline] PHST- 2023/05/27 19:12 [pubmed] PHST- 2023/05/27 07:23 [entrez] AID - 10.3171/2023.5.SPINE23336 [doi] PST - epublish SO - J Neurosurg Spine. 2023 May 26;39(3):427-437. doi: 10.3171/2023.5.SPINE23336. Print 2023 Sep 1.