{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T16:09:17Z","timestamp":1785600557554,"version":"3.56.0"},"reference-count":32,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2020,11]]},"abstract":"<jats:sec><jats:title>OBJECTIVE<\/jats:title><jats:p>Loss to follow-up has been shown to bias outcomes assessment among studies utilizing clinical registries. Here, the authors analyzed patients enrolled in a national surgical registry and compared the baseline characteristics of patients captured with those lost to follow-up at 2 years.<\/jats:p><\/jats:sec><jats:sec><jats:title>METHODS<\/jats:title><jats:p>The authors queried the Quality Outcomes Database for patients with grade I lumbar degenerative spondylolisthesis undergoing a surgical intervention between July 2014 and June 2016. Only those patients enrolled in a multisite study investigating the impact of fusion on clinical and patient-reported outcomes (PROs) among patients with grade I spondylolisthesis were evaluated.<\/jats:p><\/jats:sec><jats:sec><jats:title>RESULTS<\/jats:title><jats:p>Of the 608 patients enrolled in the study undergoing 1- or 2-level decompression (23.0%, n = 140) or 1-level fusion (77.0%, n = 468), 14.5% (n = 88) were lost to follow-up at 2 years. Patients who were lost to follow-up were more likely to be younger (59.6 \u00b1 13.5 vs 62.6 \u00b1 11.7 years, p = 0.031), be employed (unemployment rate: 53.3% [n = 277] for successful follow-up vs 40.9% [n = 36] for those lost to follow-up, p = 0.017), have anxiety (26.1% [n = 23] vs 16.3% [n = 85], p = 0.026), have higher back pain scores (7.4 \u00b1 2.9 vs 6.6 \u00b1 2.8, p = 0.010), have higher leg pain scores (7.4 \u00b1 2.5 vs 6.4 \u00b1 2.9, p = 0.003), have higher Oswestry Disability Index scores (50.8 \u00b1 18.7 vs 46 \u00b1 16.8, p = 0.018), and have lower EQ-5D scores (0.481 \u00b1 0.2 vs 0.547 \u00b1 0.2, p = 0.012) at baseline.<\/jats:p><\/jats:sec><jats:sec><jats:title>CONCLUSIONS<\/jats:title><jats:p>To execute future, high-quality studies, it is important to identify patients undergoing surgery for spondylolisthesis who might be lost to follow-up. In a large, prospective registry, the authors found that those lost to follow-up were more likely to be younger, be employed, have anxiety disorder, and have worse PRO scores.<\/jats:p><\/jats:sec>","DOI":"10.3171\/2019.12.spine191155","type":"journal-article","created":{"date-parts":[[2020,3,5]],"date-time":"2020-03-05T19:19:38Z","timestamp":1583435978000},"page":"643-651","source":"Crossref","is-referenced-by-count":11,"title":["Assessing the differences in characteristics of patients lost to follow-up at 2 years: results from the Quality Outcomes Database study on outcomes of surgery for grade I spondylolisthesis"],"prefix":"10.3171","volume":"33","author":[{"given":"Erica F.","family":"Bisson","sequence":"first","affiliation":[{"name":"Department of Neurological Surgery, University of Utah, Salt Lake City, Utah;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Praveen V.","family":"Mummaneni","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, University of California, San Francisco, California;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John","family":"Knightly","sequence":"additional","affiliation":[{"name":"Atlantic Neurosurgical Specialists, Morristown, New Jersey;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed Ali","family":"Alvi","sequence":"additional","affiliation":[{"name":"Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anshit","family":"Goyal","sequence":"additional","affiliation":[{"name":"Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew K.","family":"Chan","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, University of California, San Francisco, California;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jian","family":"Guan","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, University of Utah, Salt Lake City, Utah;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Biase","sequence":"additional","affiliation":[{"name":"Atlantic Neurosurgical Specialists, Morristown, New Jersey;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Strauss","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, University of Utah, Salt Lake City, Utah;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Steven","family":"Glassman","sequence":"additional","affiliation":[{"name":"Norton Leatherman Spine Center, Louisville, Kentucky;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kevin","family":"Foley","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, University of Tennessee, Memphis, Tennessee;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan R.","family":"Slotkin","sequence":"additional","affiliation":[{"name":"Geisinger Health System, Danville, Pennsylvania;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eric","family":"Potts","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, Goodman Campbell Brain and Spine, Indianapolis, Indiana;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark","family":"Shaffrey","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, University of Virginia Health System, Charlottesville, Virginia; 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