Change in effectiveness of mammography screening with decreasing breast cancer mortality: a population-based study.

BACKGROUND: Reductions in breast cancer mortality observed over the last three decades are partly due to improved patient management, which may erode the benefit-harm balance of mammography screening. METHODS: We estimated the numbers of women needed to invite (NNI) to prevent one breast cancer death within 10 years. Four scenarios of screening effectiveness (5-20% mortality reduction) were applied on 10,580 breast cancer deaths among Norwegian women aged 50-75 years from 1986 to 2016. We used three scenarios of overdiagnosis (10-40% excess breast cancers during screening period) for estimating ratios of numbers of overdiagnosed breast cancers for each breast cancer death prevented. RESULTS: Under the base case scenario of 20% breast cancer mortality reduction and 20% overdiagnosis, the NNI rose from 731 (95% CI: 644-830) women in 1996 to 1364 (95% CI: 1181-1577) women in 2016, while the number of women with overdiagnosed cancer for each breast cancer death prevented rose from 3.2 in 1996 to 5.4 in 2016. For a mortality reduction of 8.7%, the ratio of overdiagnosed breast cancers per breast cancer death prevented rose from 7.4 in 1996 to 14.0 in 2016. For a mortality reduction of 5%, the ratio rose from 12.8 in 1996 to 25.2 in 2016. CONCLUSIONS: Due to increasingly potent therapeutic modalities, the benefit in terms of reduced breast cancer mortality declines while the harms, including overdiagnosis, are unaffected. Future improvements in breast cancer patient management will further deteriorate the benefit-harm ratio of screening.

Well-Being, Physical Fitness, and Health Profile of 2,203 Danish Girls Aged 10-12 in Relation to Leisure-time Sports Club Activity-With Special Emphasis on the Five Most Popular Sports.

ABSTRACT: Madsen, M, Larsen, MN, Cyril, R, Møller, TK, Madsen, EE, Ørntoft, C, Lind, RR, Ryom, K, Christiansen, SR, Wikman, J, Elbe, AM, and Krustrup, P. Well-being, physical fitness, and health profile of 2,203 Danish girls aged 10-12 in relation to leisure-time sports club activity-with special emphasis on the five most popular sports. J Strength Cond Res 36(8): 2283-2290, 2022-This study investigated the relationship between leisure-time sports club activities and well-being as well as physical health parameters in 10-12-year-old Danish girls. Two thousand two hundred three girls took part in the study, which included questionnaires on participation in leisure-time sports clubs, well-being, Yo-Yo intermittent recovery level 1 children's test, long jump, balance tests, body composition, blood pressure (BP), and resting heart rate (RHR). Data were analyzed according to whether the girls participated in leisure-time sport and according to the 5 most frequently reported sports. Girls enrolled in leisure-time sports had higher physical well-being (49.3 ± 8.6 vs. 45.2 ± 8.3), psychological well-being (50.4 ± 9.0 vs. 49.4 ± 9.8), experienced more peer and social support (50.2 ± 10.0 vs. 48.9 ± 10.7), and perceived a more positive school environment (52.5 ± 8.0 vs. 50.5 ± 9.3), as well as showing higher Yo-Yo (+39%), long jump (+10%), and balance performance (+15%) than girls not involved in sport clubs. The girls active in sports clubs had higher relative muscle mass (+5%), lower fat percentage (-11%), body mass index (-5%), RHR (-3.4 b·min -1 ), and diastolic BP (-1.4 mm Hg) compared with girls not involved in sport ( p < 0.05). Girls who played soccer showed higher aerobic fitness compared with inactive girls (+67%), dancers (+39%), swimmers (+38%), and gymnasts (+16%). Gymnasts had a lower fat percentage than inactive girls (-19%), team handballers (-10%), swimmers (-12%), and soccer players (-4%). Girls participating in club-based leisure-time sports showed higher well-being and better fitness and health profiles than girls not involved in any sports club activities. Girls involved in soccer had better aerobic fitness and gymnasts a lower fat percentage.