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The Canadian Sentinel Practitioner Surveillance Network estimated vaccine effectiveness (VE) during the unusually early 2022/23 influenza A(H3N2) epidemic. Like vaccine, circulating viruses were clade 3C.2a1b.2a.2, but with genetic diversity affecting haemagglutinin positions 135 and 156, and reassortment such that H156 viruses acquired neuraminidase from clade 3C.2a1b.1a. Vaccine provided substantial protection with A(H3N2) VE of 54% (95% CI: 38 to 66) overall. VE was similar against H156 and vaccine-like S156 viruses, but with potential variation based on diversity at position 135.

> A 30-year-old woman who is new to your practice presents for a periodic health assessment. While taking the sexual history, she indicates that she has only been in relationships with other women. She questions the need for cervical cancer screening based on the advice that she had been given by

Aim: Group A streptococcus (GAS) pharyngitis is a common clinical infection with significant morbidity but remains understudied. Materials & methods: We sought to assess the rates of testing and incidence of GAS pharyngitis in Calgary, Alberta based on age and sex. Results: A total of 1,074,154 tests were analyzed (58.8% female, mean age 24.8 years) of which 16.6% were positive. Age-standardized testing and positivity was greatest in the 5–14 years age group and lowest in persons over 75 years. Females had greater rates of testing and positivity throughout. Testing rates (incidence rate ratios: 1.40, 95% CI: 1.39–1.41) and case rates (incidence rate ratios: 1.36, 95% CI: 1.33–1.39) increased over time. Conclusion: Future studies should focus on evaluating disparities in testing and treatment outcomes to optimize the approach to this infection.

> Aboriginal women, for example, have expressed concern that epidemiological risk profiles for cervical cancer used in public health campaigns could further stigmatize aboriginal women as lascivious and irresponsible. Instead, analyses are needed that recognize that high rate of cervical cancer (

Influenza virus circulation virtually ceased in Canada during the COVID-19 pandemic, re-emerging with the relaxation of restrictions in spring 2022. Using a test-negative design, the Canadian Sentinel Practitioner Surveillance Network reports 2021/22 vaccine effectiveness of 36% (95% CI: −38 to 71) against late-season illness due to influenza A(H3N2) clade 3C.2a1b.2a.2 viruses, considered antigenically distinct from the 3C.2a1b.2a.1 vaccine strain. Findings reinforce the World Health Organization’s decision to update the 2022/23 northern hemisphere vaccine to a more representative A(H3N2) clade 3C.2a1b.2a.2 strain.

> Mme Lalumiere vous demande pourquoi la clinique de radiologie ou elle a subi sa mammographie l’an dernier recommande un depistage annuel, alors que la province recommande un depistage tous les 2 ans. Elle se demande quelle recommandation est correcte. > > Le programme d’amelioration de

Le Space Command est un atout majeur pour les Etats-Unis, avec une relation privilegiee avec la France, elle-meme puissance spatiale. Les echanges d’informations sont d’autant plus nombreux que l’utilisation de l’espace par nos forces est permanente et indispensable pour garantir le succes de nos operateurs.

Population trends in PSA testing and prostate cancer incidence do not perfectly correspond. We aimed to better understand relationships between trends in PSA testing, prostate cancer incidence and mortality in Australia and factors that influence them. Methods We calculated and described standardised time trends in PSA tests, prostate biopsies, treatment of benign prostatic hypertrophy (BPH) and prostate cancer incidence and mortality in Australia in men aged 45–74, 75–84, and 85 + years. Results PSA testing increased from its introduction in 1989 to a peak in 2008 before declining in men aged 45–84 years. Prostate biopsies and cancer incidence fell from 1995 to 2000 in parallel with decrease in trans-urethral resections of the prostate (TURP) and, latterly, changes in pharmaceutical management of BPH. After 2000, changes in biopsies and incidence paralleled changes in PSA screening in men 45–84 years, while in men ≥85 years biopsy rates stabilised, and incidence fell. Prostate cancer mortality in men aged 45–74 years remained low throughout. Mortality in men 75–84 years gradually increased until mid 1990s, then gradually decreased. Mortality in men ≥ 85 years increased until mid 1990s, then stabilised. Conclusion Age specific prostate cancer incidence largely mirrors PSA testing rates. Most deviation from this pattern may be explained by less use of TURP in management of BPH and consequent less incidental cancer detection in TURP tissue specimens. Mortality from prostate cancer initially rose and then fell below what it was when PSA testing began. Its initial rise and fall may be explained by a possible initial tendency to over-attribute deaths of uncertain cause in older men with a diagnosis of prostate cancer to prostate cancer. Decreases in mortality rates were many fold smaller than the increases in incidence, suggesting substantial overdiagnosis of prostate cancer after introduction of PSA testing.

> Les femmes autochtones, par exemple, s’inquietent du fait que les profils de risque epidemiologique de cancer du col de l’uterus utilises dans les campagnes de sante publique stigmatiseraient davantage les femmes autochtones comme des femmes lascives et irresponsables. Des analyses sont

Introduction Smoking cessation activities incorporated into lung cancer screening programs have been broadly recommended, but studies to date have not shown increased quit rates associated with cessation programs in this setting. We aimed to determine the effectiveness of smoking cessation counseling in smokers presenting for lung cancer screening. Methods This study is a randomized control trial of an intensive telephone-based smoking cessation counseling intervention incorporating lung cancer screening results versus usual care (information pamphlet). All active smokers enrolled in the Alberta Lung Cancer Screening Study cohort were randomized on a 1:1 ratio with a primary endpoint of self-reported 30-day abstinence at 12 months. Results A total of 345 active smokers participating in the screening study were randomized to active smoking cessation counseling (n = 171) or control arm (n = 174). Thirty-day smoking abstinence at 12 months post-randomization was noted in 22 of 174 (12.6%) and 24 of 171 (14.0%) of participants in the control and intervention arms, respectively, a 1.4% difference (95% confidence interval: -5.9 to 8.7, p = 0.7). No statistically significant differences in 7-day or point abstinence were noted, nor were differences at 6 months or 24 months. Conclusions A telephone-based smoking cessation counseling intervention incorporating lung cancer screening results did not result in increased 12-month cessation rates versus written information alone in unselected smokers undergoing lung cancer screening. Routine referral of all current smokers to counseling-based cessation programs may not improve long-term cessation in this patient cohort. Future studies should specifically focus on this subgroup of older long-term smokers to determine the optimal method of integrating smoking cessation with lung cancer screening (clinicaltrials.gov NCT02431962).

> Ms Glow asks you why the radiology practice where she had her mammogram last year recommends annual screening, while the provincial recommendations are to screen every 2 years. She asks which is correct. > > The audit program in which you participate measures the proportion of age-eligible

OBJECTIVE: To gather information about antibiotic side effects to be used as a reference and learning resource for prescribing physicians. QUALITY OF EVIDENCE: A search of websites of various independent national agencies and recent review articles was performed. A summary table of adverse effects for each group of antimicrobials was then created, identifying allergies, short-term harms, and serious harms. The occurrence rate of each was listed when available. MAIN MESSAGE: Antimicrobials are necessary to treat various diseases. However, they cause adverse effects, such as allergic reactions, in addition to increased bacterial resistance. There is increasing awareness of the need to detect and evaluate adverse effects associated with medicines. Recently, severe and serious harms have been described for commonly used antibiotics. Therefore, current knowledge of harms from systemic oral antibiotics that are regularly used in family medicine is summarized in this article. CONCLUSION: It is difficult to identify and ascribe exact probabilities of most harms. However, all common antimicrobials create harms that must be considered when choosing whether to prescribe. Many adverse effects go unrecognized by prescribers. As side effects are inevitable, antimicrobials must be prescribed for as short a course as possible, only when the probability of benefit is greater than the risk of harm.

CKD is common, costly, and associated with adverse health outcomes. Because inexpensive treatments can slow the rate of kidney function loss, and because CKD is asymptomatic until its later stages, the idea of early detection of CKD to improve outcomes ignites enthusiasm, especially in low- and middle-income countries where renal replacement is often unavailable or unaffordable. Available data and prior experience suggest that the benefits of population-based screening for CKD are uncertain; that there is potential for harms; that screening is not a wise use of resources, even in high-income countries; and that screening has substantial opportunity costs in low- and middle-income countries that offset its hypothesized benefits. In contrast, some of the factors that diminish the value of population-based screening (such as markedly higher prevalence of CKD in people with diabetes, hypertension, and cardiovascular disease, as well as high preexisting use of kidney testing in such patients) substantially increase the appeal of searching for CKD in people with known kidney risk factors (case finding) in high-income countries as well as in low- and middle-income countries. For both screening and case finding, detection of new cases is the easiest component; the real challenge is ensuring appropriate management for a chronic disease, usually for years or even decades. This review compares and contrasts the benefits, harms, and opportunity costs associated with these two approaches to early detection of CKD. We also suggest criteria (discussed separately for high-income countries and for low- and middle-income countries) to use in assessing when countries should consider case finding versus when they should consider foregoing systematic attempts at early detection and focus on management of known cases.

Influenza vaccine effectiveness against influenza and noninfluenza respiratory viruses (NIRVs) was assessed by test-negative design using historic datasets of the community-based Canadian Sentinel Practitioner Surveillance Network, spanning 2010–2011 to 2016–2017. Vaccine significantly reduced the risk of influenza illness by >40% with no effect on coronaviruses or other NIRV risk.

BackgroundPopulation trends in PSA screening and prostate cancer incidence do not perfectly correspond. We aimed to better understand relationships between trends in PSA screening, prostate cancer incidence and mortality in Australia.MethodsDescription of age standardised time trends in PSA tests, prostate biopsies, cancer incidence and mortality within Australia for the age groups: 45-74, 75-84, and 85+ years.ResultsPSA testing increased from its introduction in 1989 to a peak in 2008. It then declined in men aged 45-84 years. Prostate biopsies and cancer incidence declined from 1995 to 2000, in parallel with decrease in trans-urethral resections of prostate (TURP). After 2000, changes in biopsies and cancer incidence paralleled PSA screening in men 45-84 years, while in men ≥85 years, biopsies stabilised and incidence declined. More recently a reduction in TURP correlated with increased Dutasteride and Tamsulosin usage. Prostate cancer mortality in men aged 45-74 years remained low throughout. Mortality in men 75-84 years gradually increased until the mid 1990s, then gradually decreased. Mortality in men ≥85 years increased until the mid 1990s, then stabilised.ConclusionsAge specific prostate cancer incidence largely mirrors PSA screening rates. Most deviation may be explained by changes in management of benign prostatic disease and incidental cancer detection. The timing of the small mortality reduction in men 75-84 years is more consistent with benefits from advances in treatment than with early detection through PSA. The large increases in prostate cancer incidence with minimal changes in mortality suggest overdiagnosis.

Interim results from Canada's Sentinel Practitioner Surveillance Network show that during a season characterised by early co-circulation of influenza A and B viruses, the 2019/20 influenza vaccine has provided substantial protection against medically-attended influenza illness. Adjusted VE overall was 58% (95% confidence interval (CI): 47 to 66): 44% (95% CI: 26 to 58) for A(H1N1)pdm09, 62% (95% CI: 37 to 77) for A(H3N2) and 69% (95% CI: 57 to 77) for influenza B viruses, predominantly B/Victoria lineage.

Vaccine effectiveness (VE) against influenza B was derived separately for Victoria and Yamagata lineages across 8 seasons (2010–2011 to 2017–2018) in Canada when trivalent influenza vaccine was predominantly used. VE was ≥50% regardless of lineage match to circulating viruses, except when the vaccine strain was unchanged from the prior season.

KEY POINTS This guideline is available in French at [www.cmaj.ca/lookup/suppl/doi:10.1503/cmaj.171430/-/DC2][1] Impaired vision is an important health burden in both developed and developing countries, particularly among older adults.[1][2] The 2006 Participation and Activity Limitation Survey

The importance of smoking cessation interventions in lung cancer screening participants has been highlighted. This study aimed to describe the smoking habits of individuals who were ineligible for lung cancer screening and to investigate whether this encounter may represent an opportunity to reduce tobacco use.Ever smokers between the ages of 55 and 80 and ≥1.5% lung cancer risk over 6 years or having smoked ≥30 pack-years and with no more than 15 years of smoking abstinence were eligible to participate in the Alberta Lung Cancer Screening Program (ALCSP). A baseline questionnaire exploring tobacco use was administered to all interested individuals as part of the eligibility determination for the program.Among 504 individuals, 254 (50.4%) met the criteria for the ALCSP and 250 (49.6%) were non-eligible for screening. Non-eligible individuals were slightly younger (mean=60.2 vs. 63.1 years, p-value0.001), and less likely to be current smokers (26.0% vs. 48.8%, p-value0.001). Non-eligible smokers had a lower degree of addiction compared to eligible group, as measured by the Fagerström Test of Nicotine Dependence (Median=4.0 vs 6.0, p-value=0.001), but still in the "moderately dependent" range for this test. There were no significant differences in motivation to quit (98.5% vs. 97.6%, p-value=0.689), or motivation to receive help with their quit attempt (89.2% vs. 90.3%, p-value=0.813) between these two groups. Only 7.7% of non-eligible and 2.4% of eligible current smokers were currently in a smoking cessation program.A significant proportion of individuals applying to, but not qualifying for a lung cancer screening program are active smokers with significant nicotine dependence. Very few are currently participating in active smoking cessation programs but almost all are interested in quitting and in receiving help with quit attempts. Future studies need to investigate the most effective approaches for smoking cessation in this substantial group of older, long-term smokers, capitalizing on their motivation to receive cessation assistance.

Summary Age-related differences in influenza B lineage infection were assessed by the community-based Canadian Sentinel Practitioner Surveillance Network between 2010–2011 and 2015–2016. Influenza B(Victoria) cases were on average 20 years younger than B(Yamagata) cases, with the latter showing a bimodal age distribution., Age-related differences in influenza B lineage detection were explored in the community-based Canadian Sentinel Practitioner Surveillance Network (SPSN) from 2010–2011 to 2015–2016. Whereas >80% of B(Victoria) cases were

Background The antigenic distance hypothesis (ADH) predicts that negative interference from prior season's influenza vaccine (v1) on the current season's vaccine (v2) protection may occur when the antigenic distance is small between v1 and v2 (v1 ≈ v2) but large between v1 and the current epidemic (e) strain (v1 ≠ e). Methods Vaccine effectiveness (VE) against medically attended, laboratory-confirmed influenza A(H3N2) illness was estimated by test-negative design during 3 A(H3N2) epidemics (2010-2011, 2012-2013, 2014-2015) in Canada. Vaccine effectiveness was derived with covariate adjustment across v2 and/or v1 categories relative to no vaccine receipt among outpatients aged ≥9 years. Prior vaccination effects were interpreted within the ADH framework. Results Prior vaccination effects varied significantly by season, consistent with the ADH. There was no interference by v1 in 2010-2011 when v1 ≠ v2 and v1 ≠ e, with comparable VE for v2 alone or v2 + v1: 34% (95% confidence interval [CI] = -51% to 71%) versus 34% (95% CI = -5% to 58%). Negative interference by v1 was suggested in 2012-2013 with nonsignificant reduction in VE when v1 ≈ v2 and v1 ≠ e: 49% (95% CI = -47% to 83%) versus 28% (95% CI = -12% to 54%). Negative effects of prior vaccination were pronounced and statistically significant in 2014-2015 when v1 ≡ v2 and v1 ≠ e: 65% (95% CI = 25% to 83%) versus -33% (95% CI = -78% to 1%). Conclusions Effects of repeat influenza vaccination were consistent with the ADH and may have contributed to findings of low VE across recent A(H3N2) epidemics since 2010 in Canada.

Introduction The Canadian Sentinel Practitioner Surveillance Network reports vaccine effectiveness (VE) for the 2018/19 influenza A(H3N2) epidemic. Aim To explain a paradoxical signal of increased clade 3C.3a risk among 35–54-year-old vaccinees, we hypothesise childhood immunological imprinting and a cohort effect following the 1968 influenza A(H3N2) pandemic. Methods We assessed VE by test-negative design for influenza A(H3N2) overall and for co-circulating clades 3C.2a1b and 3C.3a. VE variation by age in 2018/19 was compared with amino acid variation in the haemagglutinin glycoprotein by year since 1968. Results Influenza A(H3N2) VE was 17% (95% CI: −13 to 39) overall: 27% (95% CI: −7 to 50) for 3C.2a1b and −32% (95% CI: −119 to 21) for 3C.3a. Among 20–64-year-olds, VE was −7% (95% CI: −56 to 26): 6% (95% CI: −49 to 41) for 3C.2a1b and −96% (95% CI: −277 to −2) for 3C.3a. Clade 3C.3a VE showed a pronounced negative dip among 35–54-year-olds in whom the odds of medically attended illness were > 4-fold increased for vaccinated vs unvaccinated participants (p Discussion Imprinting by the first childhood influenza infection is known to confer long-lasting immunity focused toward priming epitopes. Our findings suggest vaccine mismatch may negatively interact with imprinted immunity. The immunological mechanisms for imprint-regulated effect of vaccine (I-REV) warrant investigation.

Background The influenza A(H3N2) vaccine was updated from clade 3C.3a in 2015–2016 to 3C.2a for 2016–2017 and 2017–2018. Circulating 3C.2a viruses showed considerable hemagglutinin glycoprotein diversification and the egg-adapted vaccine also bore mutations. Methods Vaccine effectiveness (VE) in 2016–2017 and 2017–2018 was assessed by test-negative design, explored by A(H3N2) phylogenetic subcluster and prior season’s vaccination history. Results In 2016–2017, A(H3N2) VE was 36% (95% confidence interval [CI], 18%–50%), comparable with (43%; 95% CI, 24%–58%) or without (33%; 95% CI, −21% to 62%) prior season’s vaccination. In 2017–2018, VE was 14% (95% CI, −8% to 31%), lower with (9%; 95% CI, −18% to 30%) versus without (45%; 95% CI, −7% to 71%) prior season’s vaccination. In 2016–2017, VE against predominant clade 3C.2a1 viruses was 33% (95% CI, 11%–50%): 18% (95% CI, −40% to 52%) for 3C.2a1a defined by a pivotal T135K loss of glycosylation; 60% (95% CI, 19%–81%) for 3C.2a1b (without T135K); and 31% (95% CI, 2%–51%) for other 3C.2a1 variants (with/without T135K). VE against 3C.2a2 viruses was 45% (95% CI, 2%–70%) in 2016–2017 but 15% (95% CI, −7% to 33%) in 2017–2018 when 3C.2a2 predominated. VE against 3C.2a1b in 2017–2018 was 37% (95% CI, −57% to 75%), lower at 12% (95% CI, −129% to 67%) for a new 3C.2a1b subcluster (n = 28) also bearing T135K. Conclusions Exploring VE by phylogenetic subcluster and prior vaccination history reveals informative heterogeneity. Pivotal mutations affecting glycosylation sites, and repeat vaccination using unchanged antigen, may reduce VE.

Background False-positive scans and resultant needless early recalls can increase harms and reduce cost-effectiveness of low-dose CT (LDCT) lung cancer screening. How LDCT scans are interpreted and classified may impact these metrics. Methods The Pan-Canadian Early Detection of Lung Cancer risk calculator was used to determine nodule risk of malignancy on baseline screening LDCTs in the Alberta Lung Cancer Screening Study, which were then classified according to Nodule Risk Classification (NRC) categories and ACR Lung Screening Reporting and Data System (Lung-RADS). Test performance characteristics and early recall rates were compared for each approach. Results In all, 775 baseline screens were analyzed. After a mean of 763 days (±203) of follow-up, lung cancer was detected in 22 participants (2.8%). No statistically significant differences in sensitivity, specificity, or area under the receiver operator characteristic curve occurred between the NRC and Lung-RADS nodule management approaches. Early recall rates were 9.2% and 9.3% for NRC and Lung-RADS, with the NRC unnecessarily recalling some ground glass nodules, and the Lung-RADS recalling many smaller solid nodules with low risk of malignancy. Conclusion Performances of both the NRC and Lung-RADS in this cohort were very good with a trend to higher sensitivity for the NRC. Early recall rates were less than 10% with each approach, significantly lower than rates using the National Lung Screening Trial cutoffs. Further reductions in early recall rates without compromising sensitivity could be achieved by increasing the NRC threshold to 20% for ground glass nodules or by applying the nodule risk calculator with a 5% threshold to 6- to 10-mm solid nodules under Lung-RADS.

Using a test-negative design, the Canadian Sentinel Practitioner Surveillance Network assessed interim 2018/19 vaccine effectiveness (VE) against predominant influenza A(H1N1)pdm09 viruses. Adjusted VE was 72% (95% confidence interval: 60 to 81) against medically attended, laboratory-confirmed influenza A(H1N1)pdm09 illness. This substantial vaccine protection was observed in all age groups, notably young children who appeared to be disproportionately affected. Sequence analysis identified heterogeneity in emerging clade 6B.1 viruses but no dominant drift variant.

Introduction Findings from the community-based Canadian Sentinel Practitioner Surveillance Network (SPSN) suggest children were more affected by the 2018/19 influenza A(H1N1)pdm09 epidemic. Aim To compare the age distribution of A(H1N1)pdm09 cases in 2018/19 to prior seasonal influenza epidemics in Canada. Methods The age distribution of unvaccinated influenza A(H1N1)pdm09 cases and test-negative controls were compared across A(H1N1)pdm09-dominant epidemics in 2018/19, 2015/16 and 2013/14 and with the general population of SPSN provinces. Similar comparisons were undertaken for influenza A(H3N2)-dominant epidemics. Results In 2018/19, more influenza A(H1N1)pdm09 cases were under 10 years old than controls (29% vs 16%; p Conclusion Children under 10 years old contributed more to outpatient A(H1N1)pdm09 medical visits in 2018/19 than prior seasonal epidemics in Canada. In 2018/19, all children under 10 years old were born after the 2009 A(H1N1)pdm09 pandemic and therefore lacked pandemic-induced immunity. In addition, more than half those born after 2009 now attend school (i.e. 5–9-year-olds), a socio-behavioural context that may enhance transmission and did not apply during prior A(H1N1)pdm09 epidemics.

To characterize the pain experienced by children with acute gastroenteritis (AGE) in the 24 hours before emergency department (ED) presentation. Secondary objectives included characterizing ED pain, discharge recommendations, overall analgesic use, and factors that influenced analgesic use and pain severity.A prospective cohort was recruited from 2 pediatric EDs (December 2014 to September 2017). Eligibility criteria included18 years of age, AGE (≥3 episodes of diarrhea or vomiting in the previous 24 hours), and symptom duration7 days at presentation.We recruited 2136 patients, median age 20.8 months (IQR 10.4, 47.4) and 45.8% (979/2136) female. In the 24 hours before enrollment, most caregivers reported moderate (28.6% [610/2136, 95% CI 26.7-30.5]) or severe (46.2% [986/2136, CI 44.0-48.3]) pain for their child. In the ED, they reported moderate (31.1% [664/2136, 95% CI 29.1-33.1]) or severe ([26.7% [571/2136, 95% CI 24.9-28.7]) pain; analgesia was provided to 21.2% (452/2131). The most common analgesics used in the ED were acetaminophen and ibuprofen. At discharge, these were also most commonly recommended. Factors associated with greater analgesia use in the ED were high pain scores during the index visit, having a primary care physician, earlier presentation to emergency care, fewer diarrheal episodes, presence of fever, and hospitalization at index visit.Most caregivers of children presenting to the ED with AGE reported moderate or severe pain, both before and during their visit. Future research should focus on the development of effective, safe, and timely pain management plans.

BACKGROUND Widespread use of prostate-specific antigen (PSA) to screen for prostate cancer began in the early 1990s. Advocates for screening assert that this has caused a decrease in prostate cancer mortality. We sought to describe secular changes in prostate cancer incidence and mortality in Canada in relation to the onset of PSA screening. METHODS Age-standardized and age-specific prostate cancer incidence (1969-2007) and mortality (1969-2009) from Public Health Agency of Canada databases were analyzed by joinpoint regression. Changes in incidence and mortality were related to introduction of PSA screening. RESULTS Prior to PSA screening, prostate cancer incidence increased from 54.2 to 99.8 per 100 000 between 1969 and 1990. Thereafter, incidence increased sharply (12.8% per year) to peak at 140.8/100 000 in 1993. After decreasing in all age groups between 1993 and 1996, incidence continued to increase for men aged less than 70 years, but decreased for older men. Age-standardized mortality was stable from 1969 to 1977, increased 1.4% per year to peak in 1995 and subsequently decreased at 3.3% per year; the decline started from 1987 in younger men (age < 60 yr). INTERPRETATION Incidence was increasing before PSA screening occurred, but rose further after it was introduced. Reductions in prostate cancer mortality began before PSA screening was widely used and were larger than could be anticipated from screening alone. These findings suggest that screening caused artifactual increase in incidence, but no more than a part of reductions in prostate cancer mortality. The reduction may be due to changing treatment or certification of death.

Background Antibiotic administration to individuals with Shiga toxin-producing Escherichia coli (STEC) infection remains controversial. We assessed if antibiotic administration to individuals with STEC infection is associated with development of hemolytic uremic syndrome (HUS). Methods The analysis included studies published up to 29 April 2015, that provided data from patients (1) with STEC infection, (2) who received antibiotics, (3) who developed HUS, and (4) for whom data reported timing of antibiotic administration in relation to HUS. Risk of bias was assessed; strength of evidence was adjudicated. HUS was the primary outcome. Secondary outcomes restricted the analysis to low-risk-of-bias studies employing commonly used HUS criteria. Pooled estimates of the odds ratio (OR) were obtained using random-effects models. Results Seventeen reports and 1896 patients met eligibility; 8 (47%) studies were retrospective, 5 (29%) were prospective cohort, 3 (18%) were case-control, and 1 was a trial. The pooled OR, including all studies, associating antibiotic administration and development of HUS was 1.33 (95% confidence interval [CI], .89-1.99; I(2) = 42%). The repeat analysis including only studies with a low risk of bias and those employing an appropriate definition of HUS yielded an OR of 2.24 (95% CI, 1.45-3.46; I(2) = 0%). Conclusions Overall, use of antibiotics was not associated with an increased risk of developing HUS; however, after excluding studies at high risk of bias and those that did not employ an acceptable definition of HUS, there was a significant association. Consequently, the use of antibiotics in individuals with STEC infections is not recommended.

Background The ability to identify bacterial pathogens that necessitate specific clinical management or public health action in children with acute gastroenteritis is crucial to patient care and public health. However, existing stool-testing guidelines offer inconsistent recommendations, and their performance characteristics are unknown. We evaluated 6 leading gastroenteritis guidelines (eg, those of the Centers for Disease Control and Prevention and Infectious Disease Society of America) that recommend when to test children’s stool for bacterial enteropathogens. Methods Via 2 emergency departments in Alberta, Canada, we enrolled 2447 children Results Outcome data were available for 2391 (97.7%) participants, and 6% (144/2391) of participants tested positive for a bacterial enteropathogen. Guideline sensitivity ranged from 25.8% (95% confidence interval [CI] 18.7–33.0%) to 66.9% (95% CI 59.3–74.6%), and varied for individual pathogens. Guideline specificity for all bacterial enteropathogens ranged from 63.6% (95% CI 61.6–65.6%) to 96.5% (95% CI 95.7–97.2%). Conclusions No guideline provided optimally balanced performance. The most sensitive guidelines missed one-third of cases and would drastically increase testing volumes. The most specific guidelines missed almost 75% of cases.

IntroductionWhile the effectiveness of cervical cancer-screening (CCS) programs is well accepted, concern is growing regarding Family physicians (FP) poor adherence to CCS guidelines resulting in over and under screening. In Canada, it is a FP responsibility to ensure that the CCS is done as per guidelines and with appropriate follow-up. Objectives and ApproachTo identify primary care physicians’ characteristics that are associated with over and under CCS for eligible women in Calgary, Alberta. We accessed the Calgary Laboratory Services data for 1475 FPs practicing in Calgary and linked it with the Physicians database of College of Physicians and Surgeons Alberta database. We then matched FP’s gender, country and year of medical school graduation, years since medical school graduation, certification in family medicine and their clinic address with their CCS testing patterns. Using doctors as their own controls, we compared data from 2010-2016 to determine practice variations in CCS patterns subsequent to guideline changes. ResultsWe analyzed approximately 2,400,000 Pap test requisitions (approx. 300,000 per year) to identify screening patterns from 2010-2016 of 1475 family practitioners practicing in Calgary. Our preliminary results identified significant variations in the test ordering patterns of FPs. Approx. half of the male FPs were not performing CCS tests on their eligible female patients. Female FPs ordered more CCS tests than their male counterparts. FP trained in North America, were ordering more pap tests than FPS trained elsewhere. Decreased CSS was also observed among FPs practicing in Northeast Calgary. Conclusion/ImplicationsWe detected three CCS patterns: FPs who never perform CSS on eligible female patients; FPs who followed recommended guidelines for performing CCS tests and FPs who performed CCS tests, not following the guidelines. To ensure appropriate use of CSS, identifying intention-behavior relationships and innovative educational interventions for FPs are required.

IntroductionCervical Cancer Screening (CCS) has reduced the incidence and mortality rates of cervical cancer (CC). However, the benefits are distributed unevenly since 30% of eligible women have not been screened within three years in Alberta. Women who have never been screened or are screened irregularly are most at risk for CC. Objectives and ApproachThe aim of this study was to understand who gets CCS and who does not, in Calgary, Alberta and analyze the CC policy implications since 2006-2016. CCS information of women aged 25-69 were obtained from Calgary Laboratory Services for the years 2006, 2011 and 2016 and matched with Canadian Census data. Negative binomial regression and Generalized Estimating Equations were used to test associations of CCS rates with socio-demographic variables for eligible women. CCS spatial trends over the years was studied using the GIS Hotspot analysis. ResultsMajor age and geographical variations were observed in CCS rates in Calgary. CCS rates in the recommended age groups varied from 40.6 % to 23.6 %. For age groups between 25 and 54, CCS rates were above 33\%, which implies that many women are having tests more than once every three years. Use was positively associated with median household income, education, Chinese ethnicity and negatively associated with ‘Black’ visible minority status. Women living in lower socio-economic areas of Calgary are screened at lower rates. Hotspot analysis maps revealed heterogeneous testing patterns in the city with relatively higher testing in the downtown, Southeast and Northwest quadrants of the city and relatively decreased CCS in the Northeast quadrant of Calgary Conclusion/ImplicationsScreening programs need to be strengthened with greater focus on including specific demographic groups and reducing overuse. Understanding current testing patterns are important in assessing the benefit to harm ratio of CCS and for monitoring and evaluation of CCS program.