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Purpose: To determine the impact of a physiciandirected, multifaceted health information technology (HIT) system on diabetes outcomes. Methods: A pre/post-interventional study. Setting and participants: The setting was Providence Primary Care Research Network in Oregon, with approximately 71 physicians caring for 117 369 patients in 13 clinic locations. The study covered Network patients with diabetes age 18 years and older. Intervention: The study intervention included implementation of the CAREMANAGER HIT system which augments an electronic medical record (EMR) by automating physician driven quality improvement interventions, including point-of-care decision support and care reminders, diabetes registry with care prompts, performance feedback with benchmarking and access to published evidence and patient educational materials. Measures: The primary clinical measures included the change in mean value for low density lipoprotein (LDL) target <100 mg/dL or 2.6 mmol/l, blood pressure (BP) target <130/80 mmHg and glycated haemoglobin (HbA1c) target <7%, and the proportion of patients meeting guideline-recommended targets for those measures. All measures were analysed using closed and open cohort approaches. Results: A total of 6072 patients were identified at baseline, 70% of whom were continuously enrolled during the 24-month study. Significant improvements were observed in all diabetes related outcomes except mean HbA1c. LDL goal attainment improved from 32% to 56% (P=0.002), while mean LDL decreased by 13 mg/dL (0.33 mmol/l, P=0.002). BP goal attainment increased significantly from 30% to 52%, with significant decreases in both mean systolic and diastolic BP. The proportion of patients with an HbA1c below 7% was higher at the end of the study (P=0.008). Mean patient satisfaction remained high, with no significant difference between baseline and follow-up. Total Relative Value Units per patient per year significantly increased as a result of an increase in the number of visits in year one and the coding complexity throughout. Conclusion: Implementation of a physician-directed, multifaceted HIT system in primary care was associated with significantly improved diabetes process and outcome measures. [ABSTRACT FROM AUTHOR]

Notable discrepancies in vulnerability to COVID-19 infection have been identified between specific population groups and regions in the USA. The purpose of this study was to estimate the likelihood of COVID-19 infection using a machine-learning algorithm that can be updated continuously based on health care data. Patient records were extracted for all COVID-19 nasal swab PCR tests performed within the Providence St. Joseph Health system from February to October of 2020. A total of 316,599 participants were included in this study, and approximately 7.7% (n = 24,358) tested positive for COVID-19. A gradient boosting model, LightGBM (LGBM), predicted risk of initial infection with an area under the receiver operating characteristic curve of 0.819. Factors that predicted infection were cough, fever, being a member of the Hispanic or Latino community, being Spanish speaking, having a history of diabetes or dementia, and living in a neighborhood with housing insecurity. A model trained on sociodemographic, environmental, and medical history data performed well in predicting risk of a positive COVID-19 test. This model could be used to tailor education, public health policy, and resources for communities that are at the greatest risk of infection., (© 2022. International Federation for Medical and Biological Engineering.)

Background: In March 2020, the caseload of patients positive for COVID-19 in hospitals began increasing rapidly, creating fear and anxiety among health care workers and concern about supplies of personal protective equipment., Objectives: To determine if implementing safety zones improves the perceptions of safety, well-being, workflow, and teamwork among hospital staff caring for patients during a pandemic., Methods: A safety zone process was implemented to designate levels of contamination risk and appropriate activities for certain areas. Zones were designated as hot (highest risk), warm (moderate risk), or cold (lowest risk). Caregivers working in the safety zones were invited to complete a survey regarding their perceptions of safety, caregiver well-being, workflow, and teamwork. Each question was asked twice to obtain caregiver opinions for the periods before and after implementation of the zones., Results: Significant improvements were seen in perceptions of caregiver safety (P < .001) and collaboration within a multidisciplinary staff (P < .001). Significant reductions in perceived staff fatigue (P = .03), perceived cross contamination (P < .001), anxiety (P < .001), and fear of exposure (P < .001) were also seen. Teamwork (P = .23) and workflow (P = .69) were not significantly affected., Conclusions: Safety zone implementation improved caregivers' perceptions of their safety, their well-being, and collaboration within the multidisciplinary staff but did not improve their perceptions of teamwork or workflow., (©2022 American Association of Critical-Care Nurses.)

Objective: With the rising incidence of thyroid cancer, a standardized approach to the evaluation of thyroid nodules is essential. Despite the presence of multiple national guidelines detailing evaluation and management of these nodules, significant variability exists in the information that is collected and reported to clinicians from diagnostic imaging. The aim of this study was to evaluate the impact of thyroid ultrasound standardization on thyroid cancer detection in a community practice setting., Design: As part of a physician-driven quality improvement project, a multidisciplinary team created an electronic worksheet to be utilized by sonographers to capture suspicious findings based on societal guidelines and agreed on institutional criteria for recommending fine needle aspiration (FNA) of thyroid nodules., Patients: For a one-year period prior to and after the intervention, all ultrasounds performed for suspected thyroid pathology, excluding patients undergoing follow-up imaging, were reviewed at two affiliated community hospitals served by a single radiology and pathology group., Measurements: The number of fine needle biopsies recommended and performed, as well as the percentage of FNAs positive for malignancy were evaluated., Results: A total of 608 and 675 ultrasounds were reviewed in pre- and post-standardization periods, respectively. Following standardization, there was a similar percentage of FNAs recommended (35% vs. 37%, p = .68), fewer FNAs per total ultrasounds performed (36% vs. 31%, p = .03), fewer FNAs performed when FNA was not explicitly recommended (9.9% vs. 2.8%, p = .000046) and an increased detection of cytology consistent with, or suspicious for, malignancy (5% vs. 11.5%, p = .0028)., Conclusions: Standardization of thyroid imaging protocol and management recommendations can reduce the number of FNAs performed and increase the percentage of positive tests in a community setting., (© 2021 John Wiley & Sons Ltd.)

Background: By mid-May 2020, there were over 1.5 million cases of (SARS-CoV-2) or COVID-19 across the U.S. with new confirmed cases continuing to rise following the re-opening of most states. Prior studies have focused mainly on clinical risk factors associated with serious illness and mortality of COVID-19. Less analysis has been conducted on the clinical, sociodemographic, and environmental variables associated with initial infection of COVID-19., Methods: A multivariable statistical model was used to characterize risk factors in 34,503cases of laboratory-confirmed positive or negative COVID-19 infection in the Providence Health System (U.S.) between February 28 and April 27, 2020. Publicly available data were utilized as approximations for social determinants of health, and patient-level clinical and sociodemographic factors were extracted from the electronic medical record., Results: Higher risk of COVID-19 infection was associated with older age (OR 1.69; 95% CI 1.41-2.02, p < 0.0001), male gender (OR 1.32; 95% CI 1.21-1.44, p < 0.0001), Asian race (OR 1.43; 95% CI 1.18-1.72, p = 0.0002), Black/African American race (OR 1.51; 95% CI 1.25-1.83, p < 0.0001), Latino ethnicity (OR 2.07; 95% CI 1.77-2.41, p < 0.0001), non-English language (OR 2.09; 95% CI 1.7-2.57, p < 0.0001), residing in a neighborhood with financial insecurity (OR 1.10; 95% CI 1.01-1.25, p = 0.04), low air quality (OR 1.01; 95% CI 1.0-1.04, p = 0.05), housing insecurity (OR 1.32; 95% CI 1.16-1.5, p < 0.0001) or transportation insecurity (OR 1.11; 95% CI 1.02-1.23, p = 0.03), and living in senior living communities (OR 1.69; 95% CI 1.23-2.32, p = 0.001)., Conclusion: sisk of COVID-19 infection is higher among groups already affected by health disparities across age, race, ethnicity, language, income, and living conditions. Health promotion and disease prevention strategies should prioritize groups most vulnerable to infection and address structural inequities that contribute to risk through social and economic policy.

Importance: Opioid use disorder (OUD) is a public health crisis in the United States, but only 5% of US physicians have obtained a Drug Addiction Treatment Act (DATA) waiver to prescribe buprenorphine to treat OUD. Increasing the number of primary care physicians (PCPs) who have obtained the waiver and are able to treat patients with OUD is of utmost importance., Objective: To determine whether a multimodal educational intervention of PCPs is associated with an increase in the number of buprenorphine waivers obtained and patients initiated into treatment in a primary care setting., Design, Setting, and Participants: This quality improvement study was conducted in primary health care clinics within a large, integrated health care system. Patients included those who had received a diagnosis of OUD, and had Providence Health Plan Medicare or Medicaid insurance. Included PCPs were divided into 2 groups: those who obtained a DATA waiver after an education intervention (uptake PCPs) vs those who did not obtain a DATA waiver (nonuptake PCPs). The study took place between January 1, 2016, and December 31, 2017. Data analyses were conducted from December 2017 to August 2019., Exposures: Multimodal educational intervention including video, in-person visits to clinical practitioner meetings by physician champions, and a primary care toolkit with training resources and clinic protocols., Main Outcomes and Measures: The number of new uptake clinics where at least 1 PCP obtained a DATA waiver, the number of new PCPs with DATA waivers, the number of patients receiving a buprenorphine prescription, and the number of patients who received 12 or more weeks of treatment., Results: Twenty-seven of 41 invited clinics implemented the intervention, and 620 PCPs were included. The number of PCPs with DATA waivers increased from 5 PCPs (0.8%) to 44 PCPs (7.1%), and the number of clinics with at least 1 buprenorphine prescriber increased from 3 clinics (7.3%) to 17 clinics (41.5%). In total, 213 patients underwent buprenorphine treatment, and 140 patients received 12 or more weeks of treatment. A total of 646 patients had Providence Health Plan Medicare or Medicaid insurance and were eligible for the study (mean [SD] age, 61.7 [16.5] years; 410 [63.5%] women). There was a statistically significant difference in treatment with buprenorphine between patients with uptake PCPs vs patients with nonuptake PCPs (23 patients [16.4%] vs 18 patients [3.5%]; odds ratio, 4.61 [95% CI, 2.32-10.51]; P = .01) after the intervention., Conclusions and Relevance: In this quality improvement study, an educational intervention was associated with an increase in the number of PCPs and clinics that could provide buprenorphine treatment for OUD and with an increase in the patients who were able to access care with medications for OUD.

Introduction: Current literature addressing the treatment of solid pseudopapillary neoplasms (SPNs) of the pancreas is limited, particularly for patients with distant metastases. We aimed to define predictive indicators of survival in a large series of patients and assess the outcome of patients with distant metastases., Methods: The National Cancer Database was queried for patients diagnosed with SPNs of the pancreas between 1998 and 2011. Single predictor univariate analyses were performed on variables including demographics, tumor characteristics, and surgery outcomes, and multivariate Cox proportional hazards survival analysis was then completed with backward elimination., Results: Overall, 340 patients were identified: 82% were female, median age was 39 years, and 84% had no comorbidities. Patients undergoing any type of surgical resection experienced long-term survival (85% 8-year survival). Patients undergoing surgical resection (n = 296) had superior survival (hazard ratio [HR] 21 for no surgery, p < 0.0001), as did patients treated at academic centers and those with private insurance (HR 3.9, p = 0.009; HR 4.9, p = 0.007). Sex, age, tumor size, presence of lymph node metastases, positive surgical margins, and presence of distant metastases were not significant predictors of survival in multivariate analysis. Of 24 patients with distant metastases, seven were treated surgically and experienced long-term survival similar to that of patients without metastases treated surgically (HR 2, p = 0.48)., Conclusion: SPNs of the pancreas are rare neoplasms with excellent overall survival; however, in a low number of patients they metastasize. Of the few patients with metastatic disease selected for resection, most experienced long-term survival.

The failure to follow national guidelines in management of various diseases has been previously established. We sought to quantify primary care providers' familiarity with primary hyperparathyroidism as it affects adherence to the 2009 National Institute of Health (NIH) consensus recommendations in treatment of primary hyperparathyroidism. A large primary care group was surveyed to determine their familiarity with the 2009 NIH consensus recommendations for management of primary hyperparathyroidism (PHPT). Retrospective review of the group's records (2009-2011) was performed to verify compliance. Survey responders included 109 clinicians, 31 per cent were familiar with all criteria for surgical intervention in asymptomatic patients and 34 per cent correctly identified appropriate surveillance testing for patients undergoing observation. Chart review identified 124 patients with PHPT. Of the patients who met NIH criteria, 34 per cent had a parathyroidectomy. Younger age, higher intact parathyroid hormone, hypercalciuria, and history of nephrolithiasis were associated with surgery in multivariable analysis. Of the observed patients, 16 per cent had appropriate surveillance studies. In conclusion, this study confirms suboptimal adherence with consensus recommendations in management of PHPT. A minority of clinicians demonstrated solid familiarity with management strategies, paralleling their treatment approach. Educational efforts may improve adherence with upcoming national recommendations.

Objectives: We hypothesized performance improvement interventions would improve COPD guideline-recommended care and decrease COPD exacerbations in primary care clinic practices., Methods: We initiated a performance improvement project in 12 clinics to improve COPD outcomes incorporating physician education, case management, web-based decision support (CareManager(TM)), and performance feedback. We collected baseline and one-year follow up data on 242 patients who had COPD with acute exacerbations. We analyzed data by two methods. First, the 12 clinics were cluster randomized to 4 intervention (117 patients) and 8 control (125 patients) clinics which all had access to CareManager(TM) but only intervention clinic physicians received case management, academic detailing, and decision support assistance. Exacerbation rates and guideline adherence were compared. Second, data from all 12 clinics were pooled in a quasi-experimental design comparing baseline and post-implementation of CareManager(TM) to determine the value of system-wide performance improvement during the study period., Results: In the randomized analysis, baseline demographics were similar. No differences (p = 0.79) occurred in exacerbation rates between intervention and control clinics although both groups had decreased numbers of exacerbations from baseline to follow up (p < 0.05). The pooled data from all 12 clinics demonstrated a reduction (p < 0.05) in mean exacerbations/patient from 2.3 (CI 2.0-2.6) during baseline to 1.4 (CI 1.1-1.7) at one-year follow up. Emergency department visits and hospitalizations/patient decreased (p = 0.003). Patients naïve at study start to depression screening, pneumococcal vaccination, inhaled control medications or smoking cessation had fewer (p < 0.05) exacerbations after these interventions., Conclusion: We observed no difference in exacerbation rates between clinics receiving case management, academic detailing, and ongoing assistance with decision support and controls. Implementation of a web-based disease management system (CareManager(TM)) along with health system-wide COPD performance improvement efforts was associated with fewer COPD exacerbations and increased adherence to guideline recommendations.

Primary hyperparathyroidism (HPT) contributes to the onset of many chronic conditions. Although parathyroidectomy is the only definitive treatment, observation remains a valid option. Over a 3-year span, a major health plan was queried for HPT and benign parathyroid neoplasm. Patients with secondary and tertiary HPT, Stage III to V kidney disease, and prior renal transplant were excluded. Patients were divided into: observation (Group 1), parathyroidectomy during the study period (Group 2), and parathyroidectomy before the study group (Group 3), and were compared with a control group of 27,092 adult members without HPT using analysis of variance. The 3-year mean total allowed expenditure for Group One (n = 559), Group Two (n = 93), and Group Three (n = 48) were $21,267, $37,043, and $14,702, respectively. Groups One and Two had significantly higher use than the nonparathyroid group (P < 0.0001), whereas that of Group Three was comparable. Group Two had the highest cost, whereas Group Three had a significantly lower cost than Group One (P 0.0001). Primary hyperparathyroidism is associated with a higher use of healthcare resources. Patients observed incurred a higher allowed expenditure than those with prior parathyroidectomy. Surgical treatment may represent a cost-effective strategy for treatment of hyperparathyroidism, although more comprehensive studies are needed to confirm these findings.

Background: Although up to 90% of patients with type 2 diabetes mellitus (T2DM) have obstructive sleep apnea (OSA), the rate at which primary care providers diagnose OSA in patients with diabetes has not been assessed., Methods: A retrospective, population-based, multiclinic study was performed to determine the proportion of patients with T2DM managed in primary care clinics who were given a diagnosis of OSA and to identify factors associated with an OSA diagnosis. Electronic health records of adult patients with a diagnosis of T2DM were reviewed for a coexisting diagnosis of OSA, and the diagnostic prevalence of OSA was compared with the expected prevalence., Results: A total of 16,066 patients with diabetes with one or more primary care office visits in 27 primary care ambulatory practices during an 18-month period from 2009 to 2010 were identified. Analysis revealed that 18% of the study population received an OSA diagnosis, which is less than the 54% to 94% prevalence reported previously. The 23% prevalence of OSA among obese study patients was lower than the expected 87% prevalence. In a logistic model, male sex, BMI, several chronic conditions, and lower low-density lipoprotein levels and hemoglobin A1c identified patients more likely to carry an OSA diagnosis (likelihood ratio, χ(2) = 1,713; P < .0001)., Conclusions: Primary care providers underdiagnose OSA in patients with T2DM. Obese men with comorbid chronic health conditions are more likely to receive a diagnosis of OSA. Efforts to improve awareness of the association of OSA with T2DM and to implement OSA screening tools should target primary care physicians.

Background: Creative, cost-effective interventions to improve the quality of care of chronic illnesses are needed. This study was designed to evaluate the impact of remote physician-pharmacist team-based care on cholesterol levels in patients with diabetes mellitus (DM)., Methods: This 2-year prospective, cluster randomized controlled trial was conducted within the Providence Primary Care Research Network in Oregon. Participants at least 18 years of age were identified by a diagnosis of DM. The intervention included remote physician-pharmacist team-based care focused on cholesterol management in DM. All clinicians in the study had access to the health information technology tool CareManager, which provided automated DM-related point-of-care prompts, a Web-based registry, and performance feedback with benchmarking. Study outcomes included the difference in low-density lipoprotein cholesterol (LDL-C) goal attainment, mean LDL-C, prescribed lipid-lowering therapy, and patient satisfaction between the intervention and control arms., Results: A total of 6963 patients with DM cared for by 68 physicians in 9 clinics were evaluated. Patients in the intervention arm were more likely to achieve their target LDL-C levels compared with controls (78% vs 50%; P = .003). The mean LDL-C level was 12 mg/dL lower in the intervention arm compared with the control arm (P < .001). The rate of LDL-C testing was significantly higher in the intervention arm compared with the control arm. Patients in the intervention arm were also 15% more likely to receive a prescription for a lipid-lowering medication (P = .008). There was no significant difference in patient satisfaction between study arms (P = .15)., Conclusion: Remotely located physician-pharmacist team-based care resulted in significantly improved LDL-C levels and goal attainment among patients with DM.

Background: Use of home monitoring technologies can enhance care coordination and improve clinical outcomes in patients with diabetes and other chronic diseases. This study was designed to explore the feasibility of incorporating a telehealth system into an existing telephonic diabetes management program utilizing clinical pharmacists., Methods: This observational study was conducted at three Providence Medical Group primary care clinics. Adults with a diagnosis of diabetes and a recent hemoglobin A1c (HbA1c) >8% were referred by their primary care provider to participate in the study. Participants utilized the telehealth system developed by Intel Corporation and were followed by clinical pharmacists who provide telephonic diabetes management. The primary clinical outcome measure was change in mean HbA1c. Secondary outcomes included blood glucose levels, participant self-management knowledge, and the degree of participant engagement., Results: Mean HbA1c level decreased by 1.3% at the study end (p = .001). Based on participant satisfaction surveys and qualitative responses, participants were satisfied with the telehealth system. Mean blood glucose values decreased significantly over the 16-week study period from 178 mg/dl [standard deviation (SD) 67] at week 1 to 163 mg/dl (SD 64) at week 16 (p = .0002). Participants entered the study with moderate to good knowledge about managing their diabetes based on three questions, and no statistically significant improvement in knowledge was found post-study., Conclusion: Telehealth technology can be a positive adjunct to the primary care team in managing diabetes or other chronic conditions to improve clinical outcomes., (© 2011 Diabetes Technology Society.)

Purpose: To evaluate the effect of patient cost-sharing on oral diabetes medication adherence and glycemic control., Design: Retrospective observational study., Methodology: Medical and pharmacy claims from a managed care plan and electronic medical records (EMR) from a large physician organization in Oregon were used to identify a cohort with diabetes. Medication adherence and mean patient cost share was obtained from claims. Glycosylated hemoglobin (A(1c)) values were obtained from an EMR database., Principal Findings: Lower mean cost share for patients was associated with higher medication adherence. Each $5 increase in patient cost share resulted in a 15 percent decrease in the adjusted odds of being adherent and a 0.1 percentage point increase in A(1c)., Conclusion: Increased medication cost share resulted in a decrease in adherence and poorer glycemic control. Employers and insurers should consider the potential consequences of increased medication cost share on diabetes-related outcomes and health care costs.

Objective: Evaluate the effectiveness of collaborative management of hypertension by primary care-pharmacist teams in community-based clinics., Study Design: A 12-month prospective, single-blind, randomized, controlled trial in the Providence Primary Care Research Network of patients with hypertension and uncontrolled blood pressure., Methods: As compared to usual primary care, intervention consisted of pharmacy practitioners participating in the active management of hypertension in the primary care office according to established collaborative treatment protocols. At baseline, there was no significant difference in blood pressure between groups. Primary outcome measures were the differences in mean systolic and diastolic blood pressures between arms at study end. Secondary measures included blood pressure goal attainment (<140/90 mmHg), hypertension-related knowledge, medication adherence, home blood pressure monitoring, resource utilization, quality of life, and satisfaction., Results: A total of 463 subjects were enrolled (n = 233 control, n = 230 intervention). Subjects receiving the intervention achieved significantly lower systolic (p = 0.007) and diastolic (p = 0.002) blood pressures compared to control (137/75 mmHg vs. 143/78 mmHg). In addition, 62% of intervention subjects achieved target blood pressure compared to 44% of control subjects (p = 0.003). The intervention group received more total office visits (7.2 vs. 4.9, p < 0.0001), however had fewer physician visits (3.2 vs. 4.7, p < 0.0001) compared to control. Intervention subjects were prescribed more antihypertensive medications (2.7 vs. 2.4, p = 0.02), but did not take more antihypertensive pills per day (2.4 vs. 2.5, p = 0.87). There were minimal differences between groups in hypertension-related knowledge, medication adherence, quality of life, or satisfaction., Conclusions: Patients randomized to collaborative primary care-pharmacist hypertension management achieved significantly better blood pressure control compared to usual care with no difference in quality of life or satisfaction.

Objective: To evaluate adherence to oral diabetes medications (ODMs) in patients with type 2 diabetes and the impact of ODM adherence on glycemic control., Study Design: Retrospective observational study., Methods: Medical and pharmacy claims from a managed care plan in Oregon were used to identify adults with diabetes who newly initiated ODM therapy (n = 2741); a subset of this cohort linked to electronic health records was used to evaluate the relationship between adherence and glycemic control (n = 249). Glycemic control was assessed based on most recent glycosylated hemoglobin (A1C) measurement within the study period., Results: Mean cohort age was 54 years; 46% initiated therapy with metformin, 39% with a sulfonylurea, and 12% with a thiazolidinedione. Mean adherence overall was 81%, and 65% of subjects had good adherence (>80%). Increasing age and comorbidity burden were associated with higher medication adherence. In the patient subset with A1C measurements, mean baseline A1C was 8%. An inverse relationship existed between ODM adherence and A1C; controlling for baseline A1C and therapy regimen, each 10% increase in ODM adherence was associated with a 0.1% A1C decrease (P = .0004)., Conclusion: Although most patients were adherent to ODM therapy, adherent patients were more likely to achieve glycemic control than nonadherent patients. Greater efforts are needed to facilitate diabetes self-management behaviors to improve patient outcomes.

Study Objectives: To examine potential threats to internal and external study validity caused by differential patient withdrawal from a randomized controlled trial evaluating pharmacist management of hypertension, to compare the characteristics of patients who withdrew with those of patients who completed the study, and to identify characteristics that predispose patients to withdraw from hypertension management., Design: Prospective, randomized, comparative study., Setting: Network of primary care clinics., Patients: Four hundred sixty-three patients with a diagnosis of hypertension and a last documented systolic blood pressure of 160 mm Hg or greater and/or diastolic blood pressure of 100 mm Hg or greater., Intervention: Patients were randomly allocated to the pharmacist intervention or usual-care (control) group. Those in the pharmacist intervention group were collaboratively managed by a primary care clinical pharmacy specialist and their primary care provider. Patients in the control group received usual care from only their primary care provider., Measurements and Main Results: Of the 463 patients, 191 (41%) withdrew from the study after randomization and 272 (59%) completed the study. Patients who withdrew from the pharmacist intervention group were similar to patients who withdrew from the usual-care group with respect to age, sex, insurance status, and chronic conditions. Patients who smoked or had commercial insurance were more likely to withdraw from the study than the other participants. However, multivariate analysis of all variables, when adjusted for the effect of the intervention, revealed that insurance status was the only variable associated with a heightened probability of withdrawal (p=0.002)., Conclusion: Although this study had a high withdrawal rate, between-group patient characteristics remained balanced. Therefore, internal validity was preserved, and outcomes from the study groups could be reliably compared. A lack of significant differences between patients who withdrew versus those who completed, with the exception of insurance status, suggests that external validity was not jeopardized.