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Background: Digital mammography has replaced film mammography in breast-screening programs globally, including Australia. This led to an increase in the rate of detection, but whether there was increased detection of clinically important cancers is uncertain. Methods: In this population-wide retrospective cohort study in New South Wales, Australia spanning 2004 to 2016 and including 4,631,656 screens, there were 22,965 cancers in women screened with film (n = 11,040) or digital mammography (n = 11,925). We examined the change in tumor characteristics overall and how these rates changed over time, accounting for changes in background rates using an interrupted time-series. Comparisons were made with unscreened women (n = 26,326) during this time. Results: We found increased detection of in situ cancer (3.36 per 10,000 screens), localized invasive, and smaller-sized breast cancers attributable to the change in mammography technology, whereas screen-detected intermediate-sized and metastatic breast cancers decreased. Rates of early-stage and intermediate-sized interval cancers increased, and late-stage (-1.62 per 10,000 screens) and large interval cancers decreased. In unscreened women, there were small increases in the temporal trends of cancers across all stages. Conclusions: At least some of the increased detection of smaller early-stage cancers may have translated into a reduction in larger and late-stage cancers, indicating beneficial detection of cancers that would have otherwise progressed. However, the increased detection of smaller early-stage and small cancers may also have increased over-diagnosis of lesions that would otherwise have not caused harm. [ABSTRACT FROM AUTHOR]

Guidelines for prostate specific antigen (PSA) testing in Australia recommend that men at average risk of prostate cancer who have been informed of the benefits and harms, and who decide to undergo regular testing, should be offered testing every 2 years from 50 to 69 years. This study aimed to estimate the benefits and harms of regular testing in this context. We constructed Policy1‐Prostate, a discrete event microsimulation platform of the natural history of prostate cancer and prostate cancer survival, and PSA testing patterns and subsequent management in Australia. The model was calibrated to pre‐PSA (before 1985) prostate cancer incidence and mortality and validated against incidence and mortality trends from 1985 to 2011 and international trials. The model predictions were concordant with trials and Australian observed incidence and mortality data from 1985 to 2011. Out of 1000 men who choose to test according to the guidelines, 36 [21‐41] men will die from prostate cancer and 126 [119‐133] men will be diagnosed with prostate cancer, compared with 50 [47‐54] and 94 [90‐98] men who do not test, respectively. During the 20 years of active PSA testing, 32.3% [25.6%‐38.8%] of all PSA‐test detected cancers are overdiagnosed cases that is, 30 [21‐42] out of 94 [83‐107] PSA‐test detected cancers. Australian men choosing to test with PSA every two years from 50 to 69 will reduce their risk of ever dying from prostate cancer and incur a risk of overdiagnosis: for every man who avoids dying from prostate cancer, two will be overdiagnosed with prostate cancer between 50 and 69 years of age. Australian men, with health professionals, can use these results to inform decision‐making about PSA testing. [ABSTRACT FROM AUTHOR]

Background: Globally, ADHD diagnoses have increased substantially and there is concern that this trend does not necessarily reflect improved detection of cases but that overdiagnosis may be occurring. We directly compared ADHD diagnoses with ADHD‐related behaviours and looked for changes across time among Australian children in a large, population‐based prospective cohort study. Methods: We conducted a secondary analysis of the Longitudinal Study of Australian Children, including 4,699 children born 1999/2000 (cohort 1) and 4,425 children born 2003/2004 (cohort 2), followed from 4 to 13 years of age. We compared pre‐diagnosis parent‐reported hyperactive/inattentive behaviour scores between newly diagnosed (incident cases) and undiagnosed children and fitted Cox's proportional hazards regression models to examine the relationship between birth cohorts 1 and 2 and the risk of incident ADHD diagnosis. Results: Cumulative incident ADHD diagnoses increased from 4.6% in cohort 1 (born in 1999/2000) to 5.6% in cohort 2 (born in 2003/2004), while hyperactive/inattentive behaviour scores remained steady. Among ADHD diagnosed children, 26.5% (88/334) recorded pre‐diagnosis behaviours in the normal range, 27.6% (n = 92) had borderline scores and 45.8% (n = 153) scored within the clinical range. Children born in 2003/2004 were more likely to be diagnosed with ADHD compared with those born in 1999/2000 (aHR = 1.33, 95% CI = 1.06–1.67, p =.012), regardless of their ADHD behaviour score (p =.972). Conclusions: Diagnostic increases were not driven by rises in hyperactive/inattentive behaviours. A quarter of all children with an ADHD diagnosis recorded pre‐diagnosis behaviours within the normal range. The increased likelihood of being diagnosed with ADHD for children from the later birth cohort was observed for children across the full range of ADHD‐related behaviours. [ABSTRACT FROM AUTHOR]

Objectives: To determine the total annual screening and further-investigation costs of investigating false-positive and true-positive mammograms in the Australian population breast-screening program. Methods: This economic analysis used aggregate-level retrospective cohort data of women screened at a breast-screening clinic. Counts and frequencies of each diagnostic workup-sequence recorded were scaled up to national figures and costed by estimating per-patient costs of procedures using screening clinic cost data. Main outcomes and measures estimated were percentage share of total annual screening and further-investigation costs for the Australian population breast-screening program of investigating false-positive and true-positive mammograms. Secondary outcomes determined were average costs of investigating each false-positive and true-positive mammogram. Sensitivity analyses involved recalculating results excluding subgroups of patients below and above the screening age range of 50–74 years. Results: Of 8235 patients, the median age was 60.35 years with interquartile range of 54.17–67.17 years. A total of 15.4% (ranging from 13.4 to 15.4% under different scenarios) of total annual screening and further-investigation costs were from investigating false-positive mammograms. This exceeded the share of costs from investigating true-positives (13%). Conclusions: We have developed a transparent and non-onerous approach for estimating the costs of false-positive and true-positive mammograms associated with the national breast-screening program. While determining an optimal balance between false-positives and true-positive rates must rely primarily on health outcomes, costs are an important consideration. We recommend that future research adopts and refines similar approaches to facilitate better monitoring of these costs, benchmark against estimates from other screening programs, and support optimal policy development. What is known about the topic? Screening mammogram results suggesting cancer later found to be wrong by follow-up testing (false-positive mammograms) consume healthcare resources unnecessarily and increases anxiety among screened women. What does this paper add? This paper estimates the share of total annual costs of Australia's national breast screening program caused by follow up testing of false-positive mammograms at approximately 15%. What are the implications for practitioners? The share of annual breast cancer screening costs from follow-up testing of false-positive mammograms can be monitored over time using the transparent and non-onerous method developed in this paper. [ABSTRACT FROM AUTHOR]