Lawrence Paszat

Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada

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Publications (172)844.42 Total impact

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    ABSTRACT: Purpose Whole-breast radiation therapy (XRT) after breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS) may decrease the risk of local recurrence, but the optimal dose regimen remains unclear. Past studies administered 50 Gy in 25 fractions (conventional); however, treatment pattern studies report that hypofractionated (HF) regimens (42.4 Gy in 16 fractions) are frequently used. We report the impact of HF (vs conventional) on the risk of local recurrence after BCS for DCIS. Methods and Materials All women with DCIS treated with BCS and XRT in Ontario, Canada from 1994 to 2003 were identified. Treatment and outcomes were assessed through administrative databases and validated by chart review. Survival analyses were performed. To account for systematic differences between women treated with alternate regimens, we used a propensity score adjustment approach. Results We identified 1609 women, of whom 971 (60%) received conventional regimens and 638 (40%) received HF. A total of 489 patients (30%) received a boost dose, of whom 143 (15%) received conventional radiation therapy and 346 (54%) received HF. The median follow-up time was 9.2 years. The median age at diagnosis was 56 years (interquartile range [IQR], 49-65 years). On univariate analyses, the 10-year actuarial local recurrence–free survival was 86% for conventional radiation therapy and 89% for HF (P=.03). On multivariable analyses, age <45 years (hazard ratio [HR] = 2.4; 95% CI: 1.6-3.4; P<.0001), high (HR=2.9; 95% CI: 1.2-7.3; P=.02) or intermediate nuclear grade (HR=2.7; 95% CI: 1.1-6.6; P=.04), and positive resection margins (HR=1.4; 95% CI: 1.0-2.1; P=.05) were associated with an increased risk of local recurrence. HF was not significantly associated with an increased risk of local recurrence compared with conventional radiation therapy on multivariate analysis (HR=0.8; 95% CI: 0.5-1.2; P=.34). Conclusions The risk of local recurrence among individuals treated with HF regimens after BCS for DCIS was similar to that among individuals treated with conventional radiation therapy.
    International journal of radiation oncology, biology, physics 09/2014; · 4.59 Impact Factor
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    ABSTRACT: Regular screening using guaiac fecal occult blood test (gFOBT) reduces mortality from colorectal cancer (CRC). The objective of this study was to determine whether the addition of a gFOBT kit to a 2nd mailed invitation compared to a 2nd mailed invitation alone increases CRC screening among eligible persons who did not respond to an initial mailed invitation. We conducted a cluster randomized controlled trial, with the physician as the unit of randomization. Participants were persons who had been invited but who had not responded to an invitation for CRC screening in an earlier pilot project. The intervention group received a mailed gFOBT kit and 2nd mailed CRC screening invitation (n=2008) while the control group received a 2nd mailed CRC screening invitation alone (n=1586). The primary outcome was the uptake of gFOBT within 6 months of the 2nd mailing. We found that the uptake of gFOBT was more than twice as high in the intervention group (20.1%) compared to the control group (9.6%). The absolute difference between the 2 groups was 10.5% (95% CI: 7.5 – 13.4%, p=<0.0001). In a subsequent adjusted analysis, participants in the intervention group were twice as likely to complete the test as those in the control group (OR=2.1; 95% CI: 1.6-2.6). These findings suggest that directly mailed gFOBT kits increases CRC screening participation among previous non-responders to a mailed invitation and that approximately 10 gFOBT kits would have to be sent by mail in order to screen 1 additional person. ( NCT01629004). © 2014 Wiley Periodicals, Inc.
    International Journal of Cancer 09/2014; · 6.20 Impact Factor
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    ABSTRACT: Since the publication of two randomized controlled trials (RCT) in 1996 demonstrating the effectiveness of fecal occult blood test (FOBT) in reducing colorectal cancer (CRC) mortality, several public health initiatives have been introduced in Ontario to promote FOBT participation. We examined the effect of these initiatives on FOBT participation and evaluated temporal trends in participation between 1994 and 2012.
    BMC Cancer 07/2014; 14(1):537. · 3.33 Impact Factor
  • Canadian journal of gastroenterology & hepatology. 07/2014;
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    ABSTRACT: OBJECTIVES:The sessile serrated adenoma/polyp (SSA/P) is increasingly recognized as an important precursor to colorectal cancer (CRC) and may contribute to proximal postcolonoscopy CRCs. Hyperplastic polyps (HPs) generally follow a more benign course than do SSA/Ps, but they have a similar histologic appearance. Our aims were to identify patient and polyp factors associated with reclassification of HPs as SSA/Ps during a central pathology review and to characterize and compare their subsequent clinical management with other polyps.METHODS:From 2003 to 2008, we prospectively enrolled asymptomatic persons aged 50-74 years in a study of screening colonoscopy. Because criteria for SSA/P diagnosis evolved over our study period, we initiated a second review of all HPs >5 mm in size in 2011, with reclassification of polyps if indicated. Rates of subsequent colonoscopies, polypectomies, and CRCs were identified.RESULTS:We enrolled 2,527 persons who underwent colonoscopy in whom 111 had HPs >5 mm. Thirty-two of the 111 participants (28.8%) with HPs >5 mm had their polyps reclassified as SSA/Ps. There were no significant differences in patient characteristics between those with reclassified SSA/Ps and those who had HPs >5 mm. SSA/Ps were more likely to be proximal (P<0.001) and larger (P<0.007) than the HPs. In all, 48.3% of those with high-risk adenomas received appropriate follow-up compared with 26.1% of those with high-risk SSA/Ps.CONCLUSIONS:Almost 1/3 of recently diagnosed HPs >5 mm were reclassified as SSA/Ps. Patients previously diagnosed with larger HPs in the proximal colon may benefit from a pathologic review to ensure appropriate diagnosis and follow-up.Am J Gastroenterol advance online publication, 8 July 2014; doi:10.1038/ajg.2014.78.
    The American journal of gastroenterology. 07/2014;
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    ABSTRACT: There is limited evidence for the effectiveness of pay for performance despite its widespread use. We assessed whether the introduction of a pay-for-performance scheme for primary care physicians in Ontario, Canada, was associated with increased cancer screening rates and determined the amounts paid to physicians as part of the program.
    The Annals of Family Medicine 07/2014; 12(4):317-23. · 4.61 Impact Factor
  • Gastrointestinal Endoscopy 05/2014; 79(5):AB118. · 5.21 Impact Factor
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    ABSTRACT: Estimating risk for advanced proximal neoplasia (APN) based on distal colon findings can help identify asymptomatic persons who should undergo examination of the proximal colon after flexible sigmoidoscopy (FS) screening. We aimed to determine the risk of APN by most advanced distal finding among an average-risk screening population. Prospective, cross-sectional study. Teaching hospital and colorectal cancer screening center. A total of 4651 asymptomatic persons at average risk for colorectal cancer aged 50 to 74 years (54.4% women [n = 2529] with a mean [± standard deviation] age of 58.4 ± 6.2 years). All participants underwent a complete colonoscopy, including endoscopic removal of all polyps. We explored associations between several risk factors and APN. Logistic regression was used to identify independent predictors of APN. A total of 142 persons (3.1%) had APN, of whom 85 (1.8%) had isolated APN (with no distal findings). APN was associated with older age, a BMI >27 kg/m(2), smoking, distal advanced adenoma and/or cancer, and distal non-advanced tubular adenoma. Those with a distal advanced neoplasm were more than twice as likely to have APN compared with those without distal lesions. Distal findings used to estimate risk of APN were derived from colonoscopy rather than FS itself. In persons at average risk for colorectal cancer, the prevalence of isolated APN was low (1.8%). Use of distal findings to predict APN may not be the most effective strategy. However, incorporating factors such as age (>65 years), sex, BMI (>27 kg/m(2)), and smoking status, in addition to distal findings, should be considered for tailoring colonoscopy recommendations. Further evaluation of risk stratification approaches in other asymptomatic screening populations is warranted.
    Gastrointestinal endoscopy 03/2014; · 6.71 Impact Factor
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    ABSTRACT: The main goal of treating ductal carcinoma in situ (dcis) is to prevent the development of invasive breast cancer. Most women are treated with breast-conserving surgery (bcs) and radiotherapy. Age at diagnosis may be a risk factor for recurrence, leading to concerns that additional treatment may be necessary for younger women. We report a population-based study of women with dcis treated with bcs and radiotherapy and an evaluation of the effect of age on local recurrence (lr). All women diagnosed with dcis in Ontario from 1994 to 2003 were identified. Treatments and outcomes were collected through administrative databases and validated by chart review. Women treated with bcs and radiotherapy were included. Survival analyses were performed to evaluate the effect of age on outcomes. We identified 5752 cases of dcis; 1607 women received bcs and radiotherapy. The median follow-up was 10.0 years. The 10-year cumulative lr rate was 27% for women younger than 45 years, 14% for women 45-50 years, and 11% for women more than 50 years of age (p < 0.0001). The 10-year cumulative invasive lr rate was 22% for women younger than 45 years, 10% for women 45-50 years, and 7% for women more than 50 years of age (p < 0.0001). On multivariate analyses, young age (<45 years) was significantly associated with lr and invasive lr [hazard ratio (hr) for lr: 2.6; 95% confidence interval (ci): 1.9 to 3.7; p < 0.0001; hr for invasive lr: 3.0; 95% ci: 2.0 to 4.4; p < 0.0001]. An age of 45-50 years was also significantly associated with invasive lr (hr: 1.6; 95% ci: 1.0 to 2.4; p = 0.04). Age at diagnosis is a strong predictor of lr in women with dcis after treatment with bcs and radiotherapy.
    Current Oncology 02/2014; 21(1):e96-e104. · 1.63 Impact Factor
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    ABSTRACT: Background: ColonCancerCheck (CCC), Canada's first province-wide colorectal cancer (CRC) screening program, was publicly launched in Ontario in April 2008. The objective of this paper is to report on key indicators of CCC Program performance since its inception. Methods: The CCC Program recommends biennial gFOBT for persons 50 to 74 years of age at average risk for CRC and colonoscopy for those at increased risk. Opportunistic screening with colonoscopy is available in Ontario. Five data sources were used to compute indicators of program performance during 2008-11. The indicators computed were FOBT participation, overdue for screening, FOBT positivity, positive predictive value (PPV) of FOBT for CRC, diagnostic follow-up, and CRC detection rate. Results: In 2011, FOBT participation was 29.8% and 46.8% of the target population was overdue for screening. FOBT positivity was higher among men (5.1%) than women (3.5%), and the PPV of FOBT for cancer was 4.3% in 2011. Follow-up colonoscopy within six months of a positive FOBT was completed by 74.6% of Program participants in 2011. The cancer detection rates for FOBT and for colonoscopy in those with a family history were 1.3 per 1,000 and 4.0 per 1,000, respectively, in 2011. Conclusions: These results provide an early indication of Program performance and provide findings relevant to other organized CRC screening programs. Impact: The greater cancer detection rate in those at increased risk due to family history who undergo colonoscopy screening suggests that a strategy of risk stratification will enhance the impact of FOBT-based screening programs.
    Cancer Epidemiology Biomarkers &amp Prevention 01/2014; · 4.56 Impact Factor
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    ABSTRACT: Background The approach for staging gastric adenocarcinoma (GC) has not been well defined, with heterogeneity in the application of staging modalities. Methods Utilizing a RAND/UCLA appropriateness methodology (RAM), a multidisciplinary expert panel of 16 physicians scored 84 GC staging scenarios. Appropriateness was scored from 1 to 9. Median appropriateness scores from 1 to 3 were considered inappropriate, 4–6 uncertain, and 7–9 appropriate. Agreement was reached when 12 or more of 16 panelists scored the scenario similarly. Appropriate scenarios were subsequently scored for necessity. Results Pretreatment TNM stage determination is necessary. Necessary staging maneuvers include esophagogastroduodenoscopy (EGD); biopsy of the tumor; documentation of tumor size, description, location, distance from gastroesophageal junction (GEJ), and any GEJ, esophageal, or duodenal involvement; if an EGD report is unclear, surgeons should repeat it to confirm tumor location. Pretreatment radiologic assessment should include computed tomography (CT)-abdomen and CT-pelvis, performed with multidetector CT scanners with 5-mm slices. Laparoscopy should be performed before resection of cT3–cT4 lesions or multivisceral resections. Laparoscopy should include inspection of the stomach, diaphragm, liver, and ovaries. Conclusions Using a RAM, we describe appropriate and necessary staging tests for the pretreatment staging evaluation of GC, as well as how some of these staging maneuvers should be conducted.
    Gastric Cancer 01/2014; · 3.99 Impact Factor
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    ABSTRACT: Objective To estimate the effect of cervical cancer screening on mortality from cervical cancer in women between the age of 20 to 69 residing in Ontario by 5 year age groups. Methods An Ontario population based case–control study of women between age 20 to 69 was performed. Cases were women who were diagnosed with cervical cancer between January 1,1998 and December 31,2008 who died from cervical cancer within this period. Controls were women without a diagnosis of cervical cancer between January 1,1998 and December 31,2008 who were alive on the case’s date of death. Exposure was defined as cervical cytology history. Conditional logistic regression was used to estimate the strength of association between mortality from cervical cancer and screening in 5 year incremental age intervals. Results We identified 1,052 cases and 10,494 controls. Less than 2.5% of women who died from cervical cancer were under the age of 30. Cervical cancer screening performed 3–36 months prior to the date of diagnosis was found to be protective of mortality from cervical cancer in women over the age of 30(odds ratio = 0.28-0.60;p < 0.05 in all strata). In women under the age of 30 cervical cancer screening was not found to be protective of mortality from cervical cancer(odds ratio = 1.58-2.43;non significant). Conclusion No association between cervical cancer screening and mortality from cervical cancer under the age of 30 was found. This could be due to there being a small or no effect or due to the fact that mortality from cervical cancer under the age of 30 is extremely rare.
    Gynecologic Oncology 01/2014; · 3.93 Impact Factor
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    ABSTRACT: A central tenet of organised cancer screening is that all persons in a target population are invited. The aims of this study were to identify participant and physician factors associated with response to mailed physician-linked invitations (study 1) and to evaluate their effectiveness in an organised colorectal cancer (CRC) screening programme (study 2). 2 studies (study 1-cohort design and study 2-matched cohort design, comprising study 1 participants and a matched control group) were conducted in the context of Ontario's organised province-wide CRC screening programme. 102 family physicians and 11 302 associated eligible patients from a technical evaluation ('the Pilot') of large-scale mailed invitations for CRC screening were included. Matched controls were randomly selected using propensity scores from among eligible patients associated with family physicians in similar practice types as the Pilot physicians. Physician-linked mailed invitation to have CRC screening. Uptake of faecal occult blood test (FOBT) within 6 months of mailed invitation (primary) and uptake of FOBT or colonoscopy within 6 months of mailed invitation (secondary). Factors significantly associated with uptake of FOBT included prior FOBT use, older participant age, greater participant comorbidity and having a female physician. In the matched analysis, Pilot participants were more likely to complete an FOBT (22% vs 8%, p<0.0001) or an FOBT or colonoscopy (25% vs 11%, p<0.0001) within 6 months of mailed invitation than matched controls. The number needed to invite to screen one additional person was 7. Centralised large-scale mailing of physician-linked invitations is feasible and effective in the context of organised CRC screening.
    BMJ Open 01/2014; 4(3):e004494. · 1.58 Impact Factor
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    ABSTRACT: To describe the perceptions of those who received invitations to the ColonCancerCheck Primary Care Invitation Pilot (the Pilot) about the mailed invitation, colorectal cancer (CRC) screening in general, and their specific screening experiences. Qualitative study with 6 focus group sessions, each 1.5 hours in length. Hamilton, Ont; Ottawa, Ont; and Thunder Bay, Ont. Screening-eligible adults, aged 50 years and older, who received a Pilot invitation for CRC screening. The focus groups were conducted by a trained moderator and were audiorecorded and transcribed verbatim. The transcripts were analyzed using grounded-theory techniques facilitated by the use of electronic software. Key themes related to the invitation letter, the role of the family physician, direct mailing of the fecal occult blood testing (FOBT) kit, and alternate CRC screening promotion strategies were identified. Specifically, participants suggested the letter content should use stronger, more powerful language to capture the reader's attention. The importance of the family physician was endorsed, although participants favoured clarification of the physician and program roles in the actual mailed invitation. Participants expressed support for directly mailing FOBT kits to individuals, particularly those with successful previous test completion, and for communication of both negative and positive screening results. This study yielded a number of important findings including strategies to optimize letter content, support for directly mailed FOBT kits, and strategies to report results that might be highly relevant to other health programs where population-based CRC screening is being considered.
    Canadian family physician Medecin de famille canadien 12/2013; 59(12):e541-e549. · 1.19 Impact Factor
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    ABSTRACT: IMPORTANCE There is growing interest in reducing the variations and deficiencies in the multidisciplinary management of gastric cancer. OBJECTIVE To define optimal treatment strategies for gastric adenocarcinoma (GC). DESIGN, SETTING, AND PARTICIPANTS RAND/UCLA Appropriateness Method involving a multidisciplinary expert panel of 16 physicians from 6 countries. INTERVENTIONS Gastrectomy, perioperative chemotherapy, adjuvant chemoradiation, surveillance endoscopy, and best supportive care. MAIN OUTCOMES AND MEASURES Panelists scored 416 scenarios regarding treatment scenarios for appropriateness from 1 (highly inappropriate) to 9 (highly appropriate). Median appropriateness scores from 1 to 3 were considered inappropriate; 4 to 6, uncertain; and 7 to 9, appropriate. Agreement was reached when 12 of 16 panelists scored the scenario similarly. Appropriate scenarios agreed on were subsequently scored for necessity. RESULTS For patients with T1N0 disease, surgery alone was considered appropriate, while there was no agreement over surgery alone for patients T2N0 disease. Perioperative chemotherapy was appropriate for patients who had T1-2N2-3 or T3-4 GC without major symptoms. Adjuvant chemoradiotherapy was classified as appropriate for T1-2N1-3 or T3-4 proximal GC and necessary for T1-2N2-3 or T3-4 distal GC. There was no agreement regarding surveillance imaging and endoscopy following gastrectomy. Surveillance endoscopy was deemed to be appropriate after endoscopic resection. For patients with metastatic GC, surgical resection was considered inappropriate for those with no major symptoms, unless the disease was limited to positive cytology alone, in which case there was disagreement. CONCLUSIONS AND RELEVANCE Patients with GC being treated with curative intent should be considered for multimodal treatment. For patients with incurable disease, surgical interventions should be considered only for the management of major bleeding or obstruction.
    JAMA surgery. 11/2013;
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    ABSTRACT: The utility of post mastectomy radiotherapy in very young women is understudied. The objective of this study was to evaluate the use of PMRT in very young women to determine the effect on recurrence and survival. All women aged ≤35 years diagnosed with invasive breast cancer from 1994 to 2003 were identified from the Ontario Cancer Registry. Patient, tumour, treatment and outcome data were abstracted from primary chart review. Local or regional recurrence was the primary endpoint with contralateral, distant recurrence/death treated as competing risks. Propensity score methods were incorporated into multivariable Cox proportional hazards models to evaluate the effect of radiation therapy on the time to local/regional, distant recurrence or death. 588 patients were identified during the study period, of which 382 were eligible for analysis. Overall, 182 (48 %) of patients sustained a recurrence after a median follow-up of 2.72 years. The use of PMRT significantly reduced locoregional recurrence (HR 0.54, 95 % CI 0.29-0.996) compared with those who did not receive PMRT. There was no significant effect of PMRT on contralateral, distant recurrences, or death without recurrence (HR 0.98, 95 % CI 0.66-1.47). Of the patients with known node status (N = 451), isolated local recurrence occurred in 5, 2.5, and 8.5 % in patients with N0, N1-3, and N4 positive nodes respectively. We have found a significant reduction in locoregional recurrence with PMRT but no survival benefit in very young women with breast cancer.
    Annals of Surgical Oncology 10/2013; · 4.12 Impact Factor
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    ABSTRACT: A relationship between higher volume providers and improved outcomes has been suggested by some studies and has been used to construct guidelines for many diseases. For gastric cancer (GC), however, optimal volume cutoffs are not clear. A multidisciplinary expert panel of 16 physicians from 6 countries scored 120 scenarios regarding provider characteristics for gastric resections for GC. Appropriateness of scenarios was scored from 1 (highly inappropriate) to 9 (highly appropriate). Median appropriateness scores from 1 to 3 were considered inappropriate, 4 to 6 uncertain, and 7 to 9 appropriate. Agreement was reached when 12 of 16 panelists scored the statement similarly. Appropriate scenarios agreed on were scored subsequently for necessity. Surgeon and hospital practice volume scenarios were evaluated. The panel felt it was inappropriate for surgeons doing ≤2 GC cases per year to perform a multivisceral resection (MVR), D2 lymphadenectomy (D2-LND), or laparoscopic total gastrectomy, and ≤6 GC cases per year for an MVR involving a pancreatoduodenectomy (MVR-PD), or endoscopic mucosal resections (EMR). It was considered appropriate for surgeons doing ≥11 GC cases per year to perform open gastrectomy or D2-LND, and ≥20 GC cases per year for any MVR, laparoscopic gastrectomy, or EMR. For hospitals, it was considered inappropriate for hospitals managing ≤4 GC cases per year to perform D2-LND or laparoscopic total gastrectomy, and ≤10 GC cases per year, for MVR-PD or EMR. Hospital volumes ≥21 cases per year was considered appropriate for any GC procedure. It was inappropriate for an MVR to be performed in a hospital without interventional radiology services and for a MVR-PD in a hospital with no level I intensive care unit. Appropriate and inappropriate provider volumes for a variety of gastric procedures have been defined by an international expert panel.
    Surgery 09/2013; · 3.37 Impact Factor
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    ABSTRACT: PURPOSE: To report the outcomes of a population of women with ductal carcinoma in situ (DCIS) treated with breast-conserving surgery and radiation and to evaluate the independent effect of boost radiation on the development of local recurrence. METHODS AND MATERIALS: All women diagnosed with DCIS and treated with breast-conserving surgery and radiation therapy in Ontario from 1994 to 2003 were identified. Treatments and outcomes were identified through administrative databases and validated by chart review. The impact of boost radiation on the development of local recurrence was determined using survival analyses. RESULTS: We identified 1895 cases of DCIS that were treated by breast-conserving surgery and radiation therapy; 561 patients received boost radiation. The cumulative 10-year rate of local recurrence was 13% for women who received boost radiation and 12% for those who did not (P=.3). The 10-year local recurrence-free survival (LRFS) rate among women who did and who did not receive boost radiation was 88% and 87%, respectively (P=.27), 94% and 93% for invasive LRFS (P=.58), and was 95% and 93% for DCIS LRFS (P=.31). On multivariable analyses, boost radiation was not associated with a lower risk of local recurrence (hazard ratio = 0.82, 95% confidence interval 0.59-1.15) (P=.25). CONCLUSIONS: Among a population of women treated with breast-conserving surgery and radiation for DCIS, additional (boost) radiation was not associated with a lower risk of local or invasive recurrence.
    International journal of radiation oncology, biology, physics 07/2013; 86(3):491-497. · 4.59 Impact Factor
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    ABSTRACT: Open-access (OA) colonoscopy may increase efficiency and decrease wait times; however, because the patient is seen for the first time at the endoscopy appointment, previous processes, such as information about the procedure, preparation and appropriate triage, may be suboptimal. To identify factors associated with OA colonoscopy and to determine the relationship between OA colonoscopy and an important quality measure, incomplete colonoscopy. A population-based analysis of all adult outpatients undergoing a first-time colonoscopy between 1997 and 2007 in Ontario was performed. Colonoscopy was considered to be OA if there were no visits in the preceding five years with the physician performing the colonoscopy. Using logistic regression, patient, physician and institution factors associated with OA colonoscopy were identified. Using propensity score matching, the relationship between OA colonoscopy and incomplete colonoscopy in 2006 was examined. A total of 1,079,259 colonoscopies were performed. Of these, 14% were OA in 1997 compared with 26% in 2007. Patients 50 to 69 years of age, those from higher-income neighbourhoods and those with less comorbidity were more likely to undergo OA colonoscopy. The odds of receiving OA colonoscopy were six times greater in a nonhospital clinic compared with a community hospital. Colonoscopy was more likely to be complete if the procedure was OA (OR 1.3 [95% CI 1.2 to 1.4]; P<0.0001). Rates of OA colonoscopy have increased substantially since 1997. Institution type was most strongly associated with OA colonoscopy. Colonoscopy completeness, a recognized quality indicator, does not appear to be compromised by OA colonoscopy.
    Canadian journal of gastroenterology = Journal canadien de gastroenterologie. 06/2013; 27(6):341-6.
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    ABSTRACT: BACKGROUND: Colorectal cancer screening (CRCS) is the only type of cancer screening where both genders reduce risks by similar proportions with identical procedures. It is an important context for examining gender differences in disease-prevention, as CRCS significantly reduces mortality via early detection and prevention. In efforts to increase screening adherence, there is increasing acknowledgment that obstructive attitudes prevent CRCS uptake. Precise identification of the gender differences in obstructive attitudes is necessary to improve uptake promotion. This study randomly sampled unscreened, screening - eligible individuals in Ontario, employing semi-structured interviews to elicit key differences in attitudinal obstructions towards colorectal cancer screening with the aim of deriving informative differences useful in planning promotions of screening uptake. METHODS: N = 81 participants (49 females, 32 males), 50 years and above, with no prior CRCS, were contacted via random-digit telephone dialing, and consented via phone-mail contact. Altogether, N = 4,459 calls were made to yield N = 85 participants (1.9% response rate) of which N = 4 participants did not complete interviews. All subjects were eligible for free-of-charge CRCS in Ontario, and each was classified, via standard interview by CRCS screening decision-stage. Telephone-based, semi-structured interviews (SSIs) were employed to investigate gender differences in CRCS attitudes, using questions focused on 5 attitudinal domains: 1) Screening experience at the time of interview; 2) Barriers to adherence; 3) Predictors of Adherence; 4) Pain-anxiety experiences related to CRCS; 5) Gender-specific experiences re: CRCS, addressing all three modalities accessible through Ontario's program: a) fecal occult blood testing; b) flexible sigmoidoscopy; c) colonoscopy. RESULTS: Interview transcript analyses indicated divergent themes related to CRCS for each gender: 1) bodily intrusion, 2) perforation anxiety, and 3) embarrassment for females and; 1) avoidant procrastination with underlying fatalism, 2) unnecessary health care and 3) uncomfortable vulnerability for males. Respondents adopted similar attitudes towards fecal occult blood testing, flexible sigmoidoscopy and colonoscopy, and were comparable in decision stage across tests. Gender differences were neither closely tied to screening stage nor modality. Women had more consistent physician relationships, were more screening-knowledgeable and better able to articulate views on screening. Men reported less consistent physician relationships, were less knowledgeable and kept decision-making processes vague and emotionally distanced (i.e. at 'arm's length'). CONCLUSIONS: Marked differences were observed in obstructive CRCS attitudes per gender. Females articulated reservations about CRCS-associated distress and males suppressed negative views while ambiguously procrastinating about the task of completing screening. Future interventions could seek to reduce CRCS-related stress (females) and address the need to overcome procrastination (males).
    BMC Public Health 05/2013; 13(1):500. · 2.08 Impact Factor

Publication Stats

4k Citations
844.42 Total Impact Points


  • 2006–2014
    • Sunnybrook Health Sciences Centre
      • • Department of Radiation Oncology
      • • Department of Medicine
      Toronto, Ontario, Canada
  • 2003–2014
    • Institute for Clinical Evaluative Sciences
      Toronto, Ontario, Canada
    • Cancer Care Ontario
      Toronto, Ontario, Canada
  • 2001–2014
    • University of Toronto
      • • Institute of Health Policy, Management and Evaluation
      • • Department of Surgery
      • • Department of Radiation Oncology
      • • Department of Medicine
      • • Institute for Clinical Evaluative Sciences
      Toronto, Ontario, Canada
  • 2013
    • Women's College Hospital
      Toronto, Ontario, Canada
    • Chinook Regional Hospital
      Lethbridge, Alberta, Canada
    • Maimonides Medical Center
      Brooklyn, New York, United States
  • 2009–2012
    • University Health Network
      • Department of Medicine
      Toronto, Ontario, Canada
    • University of British Columbia - Vancouver
      • Division of Gynaecologic Oncology
      Vancouver, British Columbia, Canada
  • 2011
    • The University of Calgary
      Calgary, Alberta, Canada
  • 1998–2008
    • Regional Integration Cancer Center
      Мендоса, Mendoza, Argentina
  • 2007
    • Dalhousie University
      Halifax, Nova Scotia, Canada
    • The University of Western Ontario
      London, Ontario, Canada
    • University of Texas MD Anderson Cancer Center
      • Department of Gynecologic Oncology
      Houston, TX, United States
  • 2006–2007
    • McMaster University
      • Department of Obstetrics and Gynaecology
      Hamilton, Ontario, Canada
  • 2003–2005
    • The Princess Margaret Hospital
      Toronto, Ontario, Canada
  • 1997–2002
    • Queen's University
      • Department of Oncology
      Kingston, Ontario, Canada
  • 2000
    • Kingston General Hospital
      Kingston, Ontario, Canada