Jun 4 - Jun 4
2018
5:00 PM - 6:00 PM
Mon - Mon

Help the Biostatistician! What You Need to Know About Estimating Power Calculations and Sample Size

Speaker

Biostatistician 3, Stanford-Surgery Policy Improvement Research & Education Ctr, Health Services Research Unit

Bio

Amber Trickey, PhD, MS, CPH is Senior Biostatistician of the S-SPIRE Center. She supports multidisciplinary teams in research design, implementation, and analysis. In over 15 years of health services research, with 8 years focused in surgery, Dr. Trickey has collaborated with diverse investigators, including attending physicians, residents, nurses, psychologists, and engineers. Dr. Trickey obtained degrees in epidemiology and biostatistics, evaluated data quality in trauma care, and led data validation studies using a surgical registry (NSQIP) and administrative claims. Dr. Trickey has contributed to public and private grants on surgical safety, simulation-based training, team communication, error disclosure, and quality metrics.

Publications

  • Rectal Prolapse: Age-Related Differences in Clinical Presentation and What Bothers Women Most. Diseases of the colon and rectum Neshatian, L., Lee, A., Trickey, A., Arnow, K., Gurland, B. 2021

    Abstract

    BACKGROUND: Rectal prolapse has a diverse symptom profile that affects patients of all ages.OBJECTIVE: We sought to identify bothersome symptoms and clinical presentation that motivated rectal prolapse patients to seek care, characterize differences in symptom severity with age, and determine factors associated with bothersome symptoms.DESIGN: Retrospective analysis of a prospectively maintained registry.SETTINGS: Tertiary referral academic center.PATIENTS: 129 consecutive women with full thickness rectal prolapse.MAIN OUTCOME MEASURES: Primary bothersome symptoms, 5-item Cleveland Clinic/Wexner Fecal Incontinence questionnaire, 5-item Obstructed Defecation Syndrome questionnaire. Patients were categorized by age<65 vs. age≥65 years.RESULTS: Cleveland Clinic/Wexner Fecal Incontinence score>9 was more common in older patients (87% vs 60%, p=.002). Obstructed Defecation Syndrome score>8 was more common in younger patients (57% vs 28%, p<.001). Older patients were more likely than younger patients to report bothersome symptoms of pain (38% vs 19%, p=.021) and bleeding (12% vs 2%, p=.046). Mucus discharge was reported by most patients (older, 72% vs younger, 66%, p=.54) but was bothersome for only 18%, regardless of age. Older patients had more severe prolapse expression than younger patients (at rest, 33% vs 11%; during activity, 26% vs 19%; only with defecation, 40% vs 64%, p=.006). Older patients were more likely to seek care within 6 months of prolapse onset (29% vs 11%, p=.056). Upon multivariable regression, increasing age, narcotic use and non-protracting prolapse at rest were associated with reporting pain as a primary complaint.LIMITATIONS: Single center; small sample size.CONCLUSIONS: Rectal prolapse-related bothersome symptoms and healthcare utilization differ by age. Although rectal pain is often not commonly associated with prolapse, it bothers many women and motivates older women to undergo evaluation. Patient-reported functional questionnaires may not reflect patients' primary concerns regarding specific symptoms and could benefit from supplementation with questionnaires to elicit individualized symptom priorities. See Video Abstract at http://links.lww.com/DCR/B492 .

    View details for DOI 10.1097/DCR.0000000000001843

    View details for PubMedID 33496475

  • Patient Factors Associated With Parathyroidectomy in Older Adults With Primary Hyperparathyroidism. JAMA surgery Seib, C. D., Suh, I., Meng, T., Trickey, A., Smith, A. K., Finlayson, E., Covinsky, K. E., Kurella Tamura, M., Kebebew, E. 2021

    Abstract

    Importance: Parathyroidectomy provides definitive management for primary hyperparathyroidism (PHPT), reducing the risk of subsequent fracture, nephrolithiasis, and chronic kidney disease (CKD), but its use among older adults in the US is unknown.Objective: To identify patient characteristics associated with the use of parathyroidectomy for the management of PHPT in older adults.Design, Setting, and Participants: This population-based, retrospective cohort study used 100% Medicare claims from beneficiaries with an initial diagnosis of PHPT from January 1, 2006, to December 31, 2016. Patients were considered to meet consensus guideline criteria for parathyroidectomy based on diagnosis codes indicating osteoporosis, nephrolithiasis, or stage 3 CKD. Multivariable logistic regression was used to identify patient characteristics associated with parathyroidectomy. Data were analyzed from February 11, 2020, to October 8, 2020.Main Outcomes and Measures: The primary outcome was parathyroidectomy within 1 year of diagnosis.Results: Among 210 206 beneficiaries with an incident diagnosis of PHPT (78.8% women; mean [SD] age, 75.3 [6.8] years), 63 136 (30.0%) underwent parathyroidectomy within 1 year of diagnosis. Among the subset of patients who met consensus guideline criteria for operative management (n=131 723), 38 983 (29.6%) were treated with parathyroidectomy. Patients treated operatively were younger (mean [SD] age, 73.5 [5.7] vs 76.0 [7.1] years) and more likely to be White (90.1% vs 86.0%), to be robust or prefrail (92.1% vs 85.7%), and to have fewer comorbidities (Charlson Comorbidity Index score of 0 or 1, 54.6% vs 44.1%), in addition to being more likely to live in socioeconomically disadvantaged (46.9% vs 40.3%) and rural (18.1% vs 13.6%) areas (all P<.001). On multivariable analysis, increasing age had a strong inverse association with parathyroidectomy among patients aged 76 to 85 years (unadjusted rate, 25.9%; odds ratio [OR], 0.68 [95% CI, 0.67-0.70]) and older than 85 years (unadjusted rate, 11.2%; OR, 0.27 [95% CI, 0.26-0.29]) compared with those aged 66 to 75 years (unadjusted rate, 35.6%), as did patients with moderate to severe frailty (unadjusted rate, 18.9%; OR, 0.60 [95% CI, 0.56-0.64]) compared with robust patients (unadjusted rate, 36.1%) and those with a Charlson Comorbidity Index score of 2 or greater (unadjusted rate, 25.9%; OR, 0.77 [95% CI, 0.75-0.79]) compared with a Charlson Comorbidity Index score of 0 (unadjusted rate, 37.0%). With regard to operative guidelines, a history of nephrolithiasis increased the odds of parathyroidectomy (OR, 1.43 [95% CI, 1.39-1.47]); stage 3 CKD decreased the odds of parathyroidectomy (OR, 0.71 [95% CI, 0.68-0.74]); and osteoporosis showed no association (OR, 1.01 [95% CI, 0.99-1.03]).Conclusions and Relevance: In this cohort study, most older adults with PHPT did not receive definitive treatment with parathyroidectomy. Older age, frailty, and multimorbidity were associated with nonoperative management, and guideline recommendations had minimal effect on treatment decisions. Further research is needed to identify barriers to surgical care and develop tools to target parathyroidectomy to older adults most likely to benefit.

    View details for DOI 10.1001/jamasurg.2020.6175

    View details for PubMedID 33404646

  • Association Between Patient Frailty and Postoperative Mortality Across Multiple Noncardiac Surgical Specialties. JAMA surgery George, E. L., Hall, D. E., Youk, A., Chen, R., Kashikar, A., Trickey, A. W., Varley, P. R., Shireman, P. K., Shinall, M. C., Massarweh, N. N., Johanning, J., Arya, S. 2020: e205152

    Abstract

    Importance: Frailty is an important risk factor for postoperative mortality. Whether the association between frailty and mortality is consistent across all surgical specialties, especially those predominantly performing lower stress procedures, remains unknown.Objective: To examine the association between frailty and postoperative mortality across surgical specialties.Design, Setting, and Participants: A cohort study was conducted across 9 noncardiac specialties in hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) and Veterans Affairs Surgical Quality Improvement Program (VASQIP) from January 1, 2010, through December 31, 2014, using multivariable logistic regression to evaluate the association between frailty and postoperative mortality. Data analysis was conducted from September 15, 2019, to April 30, 2020. Patients 18 years or older undergoing noncardiac procedures were included.Exposures: Risk Analysis Index measuring preoperative frailty categorized patients as robust (Risk Analysis Index ≤20), normal (21-29), frail (30-39), or very frail (≥40). Operative Stress Score (OSS) categorized procedures as low (1-2), moderate (3), and high (4-5) stress. Specialties were categorized by case-mix as predominantly low intensity (>75% OSS 1-2), moderate intensity (50%-75%), or high intensity (<50%).Main Outcomes and Measures: Thirty-day (both measures) and 180-day (VASQIP only) postoperative mortality.Results: Of the patients evaluated in NSQIP (n=2 339 031), 1 309 795 were women (56.0%) and mean (SD) age was 56.49 (16.4) years. Of the patients evaluated in VASQIP (n=426 578), 395 761 (92.78%) were men and mean (SD) age was 61.1 (12.9) years. Overall, 30-day mortality was 1.2% in NSQIP and 1.0% in VASQIP, and 180-day mortality in VASQIP was 3.4%. Frailty and OSS distributions differed substantially across the 9 specialties. Patterns of 30-day mortality for frail and very frail patients were similar in NSQIP and VASQIP for low-, moderate-, and high-intensity specialties. Frailty was a consistent, independent risk factor for 30- and 180-day mortality across all specialties. For example, in NSQIP, for plastic surgery, a low-intensity specialty, the odds of 30-day mortality in very frail (adjusted odds ratio [aOR], 27.99; 95% CI, 14.67-53.39) and frail (aOR, 5.1; 95% CI, 3.03-8.58) patients were statistically significantly higher than for normal patients. This was also true in neurosurgery, a moderate-intensity specialty, for very frail (aOR, 9.8; 95% CI, 7.68-12.50) and frail (aOR, 4.18; 95% CI, 3.58-4.89) patients and in vascular surgery, a high-intensity specialty, for very frail (aOR, 10.85; 95% CI, 9.83-11.96) and frail (aOR, 3.42; 95% CI, 3.19-3.67) patients.Conclusions and Relevance: In this study, frailty was associated with postoperative mortality across all noncardiac surgical specialties regardless of case-mix. Preoperative frailty assessment could be implemented across all specialties to facilitate risk stratification and shared decision-making.

    View details for DOI 10.1001/jamasurg.2020.5152

    View details for PubMedID 33206156

  • Multidisciplinary Preoperative Management of Clinically Complex Patients Results in Delay to Bariatric Surgery Bandle, J., Trickey, A., Chen, R., Eisenberg, D. ELSEVIER SCIENCE INC. 2020: E2–E3
  • Undertreatment of primary hyperparathyroidism in a privately insured US population: Decreasing utilization of parathyroidectomy despite expanding surgical guidelines. Surgery Seib, C. D., Meng, T., Suh, I., Cisco, R. M., Lin, D. T., Morris, A. M., Trickey, A. W., Kebebew, E. 2020

    Abstract

    BACKGROUND: Primary hyperparathyroidism is associated with substantial morbidity, including osteoporosis, nephrolithiasis, and chronic kidney disease. Parathyroidectomy can prevent these sequelae but is poorly utilized in many practice settings.METHODS: We performed a retrospective cohort study using the national Optum de-identified Clinformatics Data Mart Database. We identified patients aged ≥35 with a first observed primary hyperparathyroidism diagnosis from 2004 to 2016. Multivariable logistic regression was used to determine patient/provider characteristics associated with parathyroidectomy.RESULTS: Of 26,522 patients with primary hyperparathyroidism, 10,101 (38.1%) underwent parathyroidectomy. Of the 14,896 patients with any operative indication, 5,791 (38.9%) underwent parathyroidectomy. Over time, there was a decreasing trend in the rate of parathyroidectomy overall (2004: 54.4% to 2016: 32.4%, P < .001) and among groups with and without an operative indication. On multivariable analysis, increasing age and comorbidities were strongly, inversely associated with parathyroidectomy (age 75-84, odds ratio 0.50 [95% confidence interval 0.45-0.55]; age ≥85, odds ratio 0.21 [95% confidence interval 0.17-0.26] vs age 35-49; Charlson Comorbidity Index ≥2 vs 0 odds ratio 0.62 [95% confidence interval 0.58-0.66]).CONCLUSION: The majority of US privately insured patients with primary hyperparathyroidism are not treated with parathyroidectomy. Having an operative indication only modestly increases the likelihood of parathyroidectomy. Further research is needed to address barriers to treatment and the gap between guidelines and clinical care in primary hyperparathyroidism.

    View details for DOI 10.1016/j.surg.2020.04.066

    View details for PubMedID 32654861

Location

Li Ka Shing Learning and Knowledge Center
291 Campus Drive, Room LK120
Stanford, CA 94305
USA

Loading Map...

Li Ka Shing Learning and Knowledge Center

291 Campus Drive, Room LK120
Stanford CA, 94305
Get Directions