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1.
Health Sci Rep ; 6(8): e1433, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37645032

ABSTRACT

Background and Aims: Prognostic models provide evidence-based predictions and estimates of future outcomes, facilitating decision-making, patient care, and research. A few of these models have been externally validated, leading to uncertain reliability and generalizability. This study aims to externally validate four models to assess their transferability and usefulness in clinical practice. The models include the respiratory index of severity in children (RISC)-Malawi model and three other models by Lowlavaar et al. Methods: The study used data from the Clinical Information Network (CIN) to validate the four models where the primary outcome was in-hospital mortality. 163,329 patients met eligibility criteria. Missing data were imputed, and the logistic function was used to compute predicted risk of in-hospital mortality. Models' discriminatory ability and calibration were determined using area under the curve (AUC), calibration slope, and intercept. Results: The RISC-Malawi model had 50,669 pneumonia patients who met the eligibility criteria, of which the case-fatality ratio was 4406 (8.7%). Its AUC was 0.77 (95% CI: 0.77-0.78), whereas the calibration slope was 1.04 (95% CI: 1.00 -1.06), and calibration intercept was 0.81 (95% CI: 0.77-0.84). Regarding the external validation of Lowlavaar et al. models, 10,782 eligible patients  were included, with an in-hospital mortality rate of 5.3%. The primary model's AUC was 0.75 (95% CI: 0.72-0.77), the calibration slope was 0.78 (95% CI: 0.71-0.84), and the calibration intercept was 0.37 (95% CI: 0.28-0.46). All models markedly underestimated the risk of mortality. Conclusion: All externally validated models exhibited either underestimation or overestimation of the risk as judged from calibration statistics. Hence, applying these models with confidence in settings other than their original development context may not be advisable. Our findings strongly suggest the need for recalibrating these model to enhance their generalizability.

2.
Paediatr Perinat Epidemiol ; 37(4): 313-321, 2023 05.
Article in English | MEDLINE | ID: mdl-36745113

ABSTRACT

BACKGROUND: In an external validation study, model recalibration is suggested once there is evidence of poor model calibration but with acceptable discriminatory abilities. We identified four models, namely RISC-Malawi (Respiratory Index of Severity in Children) developed in Malawi, and three other predictive models developed in Uganda by Lowlaavar et al. (2016). These prognostic models exhibited poor calibration performance in the recent external validation study, hence the need for recalibration. OBJECTIVE: In this study, we aim to recalibrate these models using regression coefficients updating strategy and determine how much their performances improve. METHODS: We used data collected by the Clinical Information Network from paediatric wards of 20 public county referral hospitals. Missing data were multiply imputed using chained equations. Model updating entailed adjustment of the model's calibration performance while the discriminatory ability remained unaltered. We used two strategies to adjust the model: intercept-only and the logistic recalibration method. RESULTS: Eligibility criteria for the RISC-Malawi model were met in 50,669 patients, split into two sets: a model-recalibrating set (n = 30,343) and a test set (n = 20,326). For the Lowlaavar models, 10,782 patients met the eligibility criteria, of whom 6175 were used to recalibrate the models and 4607 were used to test the performance of the adjusted model. The intercept of the recalibrated RISC-Malawi model was 0.12 (95% CI 0.07, 0.17), while the slope of the same model was 1.08 (95% CI 1.03, 1.13). The performance of the recalibrated models on the test set suggested that no model met the threshold of a perfectly calibrated model, which includes a calibration slope of 1 and a calibration-in-the-large/intercept of 0. CONCLUSIONS: Even after model adjustment, the calibration performances of the 4 models did not meet the recommended threshold for perfect calibration. This finding is suggestive of models over/underestimating the predicted risk of in-hospital mortality, potentially harmful clinically. Therefore, researchers may consider other alternatives, such as ensemble techniques to combine these models into a meta-model to improve out-of-sample predictive performance.


Subject(s)
Child Mortality , Resource-Limited Settings , Humans , Child , Prognosis , Hospital Mortality , Hospitals
3.
PLoS One ; 14(7): e0219813, 2019.
Article in English | MEDLINE | ID: mdl-31339919

ABSTRACT

BACKGROUND: Despite considerable efforts to prevent HIV and other sexually transmitted infections (STI) among female sex workers (FSW), other sexual and reproductive health (SRH) needs, such preventing unintended pregnancies, among FSW have received far less attention. Programs targeting FSW with comprehensive, accessible services are needed to address their broader SRH needs. This study tested the effectiveness of an intervention to increase dual contraceptive method use to prevent STIs, HIV and unintended pregnancy among FSW attending services in drop-in centers (DIC) in two cities in Kenya. The intervention included enhanced peer education, and routine screening for family planning (FP) needs plus expanded non-condom FP method availability in the DIC. METHODS: We conducted a two-group, pre-/posttest, quasi-experimental study with 719 FSW (360 intervention group, 359 comparison group). Participants were interviewed at baseline and 6 months later to examine changes in condom and non-condom FP method use. RESULTS: The intervention had a significant positive effect on non-condom, FP method use (OR = 1.38, 95%CI (1.04, 1.83)), but no effect on dual method use. Consistent condom use was reported to be high; however, many women also reported negotiating condom use with both paying and non-paying partners as difficult or very difficult. The strongest predictor of consistent condom use was partner type (paying versus non-paying/emotional); FSW reported both paying and non-paying partners also influence non-condom contraceptive use. Substantial numbers of FSW also reported experiencing sexual violence by both paying and non-paying partners. CONCLUSIONS: Self-reported difficulties with consistent condom use and the sometimes dangerous conditions under which they work leave FSW vulnerable to unintended pregnancy STIs/HIV. Adding non-barrier FP methods to condoms is crucial to curb unintended pregnancies and their potential adverse health, social and economic consequences. Findings also highlight the need for additional strategies beyond condoms to reduce HIV and STI risk among FSW. TRIAL REGISTRATION: Clinicaltrials.gov NCT01957813.


Subject(s)
Acquired Immunodeficiency Syndrome/prevention & control , Contraception/standards , Preventive Health Services/standards , Sex Education/standards , Sex Workers/statistics & numerical data , Adolescent , Adult , Facilities and Services Utilization/statistics & numerical data , Female , Humans , Kenya , Middle Aged , Pregnancy , Preventive Health Services/methods , Preventive Health Services/statistics & numerical data , Reproductive Health , Sex Workers/education
4.
Contraception ; 94(1): 34-9, 2016 07.
Article in English | MEDLINE | ID: mdl-26976072

ABSTRACT

OBJECTIVE: Female sex workers (FSWs) need access to contraceptive services, yet programs often focus on HIV prevention and less on the broader sexual and reproductive health needs of FSWs. We aimed to identify barriers to accessing contraceptive services among FSWs and preferences for contraceptive service delivery options among FSWs and health care providers (HCPs) in order to inform a service delivery intervention to enhance access to and use of contraceptives for FSWs in Kenya. STUDY DESIGN: Twenty focus group discussions were conducted with FSWs and HCPs in central Kenya. RESULTS: Three barriers were identified that limited the ability of FSWs to access contraceptive services: (1) an unsupportive clinic infrastructure, which consisted of obstructive factors such as long wait times, fees, inconvenient operating hours and perceived compulsory HIV testing; (2) discriminatory provider-client interactions, where participants believed negative and differential treatment from female and male staff members impacted FSWs' willingness to seek medical services; and (3) negative partner influences, including both nonpaying and paying partners. Drop-in centers followed by peer educators and health care facilities were identified as preferred service delivery options. CONCLUSIONS: FSWs may not be able to regularly access contraceptive services until interpersonal (male partners) and structural (facilities and providers) barriers are addressed. Alternative delivery options, such as drop-in centers coupled with peer educators, may be an approach worth evaluating. IMPLICATIONS STATEMENT: An unsupportive clinic infrastructure, discriminatory provider-client interactions and negative partner influences are barriers to FSWs accessing the contraception services they need. Alternative service delivery options, such integrating contraceptive service delivery at drop-in centers designed for FSWs and information delivery through peer educators, might provide improved access and better service quality to FSWs seeking contraception.


Subject(s)
Attitude of Health Personnel , Contraception/statistics & numerical data , Health Personnel , Health Services Needs and Demand , Patient Preference , Sex Workers , Adolescent , Adult , Female , Focus Groups , HIV Infections/prevention & control , Humans , Kenya , Male , Mass Screening , Middle Aged , Patient Acceptance of Health Care , Qualitative Research , Sexual Partners , Young Adult
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