Systematic review of prognostic models in traumatic brain injury

BACKGROUND: Traumatic brain injury (TBI) is a leading cause of death and disability world-wide. The ability to accurately predict patient outcome after TBI has an important role in clinical practice and research. Prognostic models are statistical models that combine two or more items of patient data to predict clinical outcome. They may improve predictions in TBI patients. Multiple prognostic models for TBI have accumulated for decades but none of them is widely used in clinical practice. The objective of this systematic review is to critically assess existing prognostic models for TBI METHODS: Studies that combine at least two variables to predict any outcome in patients with TBI were searched in PUBMED and EMBASE. Two reviewers independently examined titles, abstracts and assessed whether each met the pre-defined inclusion criteria. RESULTS: A total of 53 reports including 102 models were identified. Almost half (47%) were derived from adult patients. Three quarters of the models included less than 500 patients. Most of the models (93%) were from high income countries populations. Logistic regression was the most common analytical strategy to derived models (47%). In relation to the quality of the derivation models (n:66), only 15% reported less than 10% pf loss to follow-up, 68% did not justify the rationale to include the predictors, 11% conducted an external validation and only 19% of the logistic models presented the results in a clinically user-friendly way CONCLUSION: Prognostic models are frequently published but they are developed from small samples of patients, their methodological quality is poor and they are rarely validated on external populations. Furthermore, they are not clinically practical as they are not presented to physicians in a user-friendly way. Finally because only a few are developed using populations from low and middle income countries, where most of trauma occurs, the generalizability to these setting is limited

Effectiveness of routine third trimester ultrasonography to reduce adverse perinatal outcomes in low risk pregnancy (the IRIS study): nationwide, pragmatic, multicentre, stepped wedge cluster randomised trial

Objectives To investigate the effectiveness of routine ultrasonography in the third trimester in reducing adverse perinatal outcomes in low risk pregnancies compared with usual care and the effect of this policy on maternal outcomes and obstetric interventions. Design Pragmatic, multicentre, stepped wedge cluster randomised trial. Setting 60 midwifery practices in the Netherlands. Participants 13 046 women aged 16 years or older with a low risk singleton pregnancy. Interventions 60 midwifery practices offered usual care (serial fundal height measurements with clinically indicated ultrasonography). After 3, 7, and 10 months, a third of the practices were randomised to the intervention strategy. As well as receiving usual care, women in the intervention strategy were offered two routine biometry scans at 28-30 and 34-36 weeks’ gestation. The same multidisciplinary protocol for detecting and managing fetal growth restriction was used in both strategies. Main outcome measures The primary outcome measure was a composite of severe adverse perinatal outcomes: perinatal death, Apgar score <4, impaired consciousness, asphyxia, seizures, assisted ventilation, septicaemia, meningitis, bronchopulmonary dysplasia, intraventricular haemorrhage, periventricular leucomalacia, or necrotising enterocolitis. Secondary outcomes were two composite measures of severe maternal morbidity, and spontaneous labour and birth. Results Between 1 February 2015 and 29 February 2016, 60 midwifery practices enrolled 13 520 women in mid-pregnancy (mean 22.8 (SD 2.4) weeks’ gestation). 13 046 women (intervention n=7067, usual care n=5979) with data based on the national Dutch perinatal registry or hospital records were included in the analyses. Small for gestational age at birth was significantly more often detected in the intervention group than in the usual care group (179 of 556 (32%) v 78 of 407 (19%), P<0.001). The incidence of severe adverse perinatal outcomes was 1.7% (n=118) for the intervention strategy and 1.8% (n=106) for usual care. After adjustment for confounders, the difference between the groups was not significant (odds ratio 0.88, 95% confidence interval 0.70 to 1.20). The intervention strategy showed a higher incidence of induction of labour (1.16, 1.04 to 1.30) and a lower incidence of augmentation of labour (0.78, 0.71 to 0.85). Maternal outcomes and other obstetric interventions did not differ between the strategies. Conclusion In low risk pregnancies, routine ultrasonography in the third trimester along with clinically indicated ultrasonography was associated with higher antenatal detection of small for gestational age fetuses but not with a reduced incidence of severe adverse perinatal outcomes compared with usual care alone. The findings do not support routine ultrasonography in the third trimester for low risk pregnancies. Trial registration Netherlands Trial Register NTR4367

Developing risk prediction models for type 2 diabetes: a systematic review of methodology and reporting

<p>Abstract</p> <p>Background</p> <p>The World Health Organisation estimates that by 2030 there will be approximately 350 million people with type 2 diabetes. Associated with renal complications, heart disease, stroke and peripheral vascular disease, early identification of patients with undiagnosed type 2 diabetes or those at an increased risk of developing type 2 diabetes is an important challenge. We sought to systematically review and critically assess the conduct and reporting of methods used to develop risk prediction models for predicting the risk of having undiagnosed (prevalent) or future risk of developing (incident) type 2 diabetes in adults.</p> <p>Methods</p> <p>We conducted a systematic search of PubMed and EMBASE databases to identify studies published before May 2011 that describe the development of models combining two or more variables to predict the risk of prevalent or incident type 2 diabetes. We extracted key information that describes aspects of developing a prediction model including study design, sample size and number of events, outcome definition, risk predictor selection and coding, missing data, model-building strategies and aspects of performance.</p> <p>Results</p> <p>Thirty-nine studies comprising 43 risk prediction models were included. Seventeen studies (44%) reported the development of models to predict incident type 2 diabetes, whilst 15 studies (38%) described the derivation of models to predict prevalent type 2 diabetes. In nine studies (23%), the number of events per variable was less than ten, whilst in fourteen studies there was insufficient information reported for this measure to be calculated. The number of candidate risk predictors ranged from four to sixty-four, and in seven studies it was unclear how many risk predictors were considered. A method, not recommended to select risk predictors for inclusion in the multivariate model, using statistical significance from univariate screening was carried out in eight studies (21%), whilst the selection procedure was unclear in ten studies (26%). Twenty-one risk prediction models (49%) were developed by categorising all continuous risk predictors. The treatment and handling of missing data were not reported in 16 studies (41%).</p> <p>Conclusions</p> <p>We found widespread use of poor methods that could jeopardise model development, including univariate pre-screening of variables, categorisation of continuous risk predictors and poor handling of missing data. The use of poor methods affects the reliability of the prediction model and ultimately compromises the accuracy of the probability estimates of having undiagnosed type 2 diabetes or the predicted risk of developing type 2 diabetes. In addition, many studies were characterised by a generally poor level of reporting, with many key details to objectively judge the usefulness of the models often omitted.</p

De rol van klinisch verloskundigen bij bevallingen in de tweede lijn.

In toenemende mate hebben ziekenhuizen de laatste jaren verloskundigen in dienst genomen, om een deel van het werk op de verloskamers op zich te nemen, om een rol te spelen in de begeleiding van de zwangerschappen in de tweede lijn en om een bijdrage te leveren aan de opleiding van artsen, verpleegkundigen en anderen (NVOG, 2000; NVOG 2008; PRN, 2009). Een onderzoek door het NIVEL, louter op basis van LVR-2 cijfers, maakt zichtbaar wat de bijdrage is van de klinische verloskundigen in het totaal van de tweedelijns verloskundige zorg. (aut.ref.

Karakteristieken van zwangere vrouwen en de zwangerschap in Europees perspectief

Perinatale mortaliteit en morbiditeit hangen samen met sociale en demografische kenmerken van de populatie. Om verschillen in ongunstige zwangerschapsuitkomsten tussen Europese landen te kunnen inter- preteren is het daarom van belang kenmerken van zwangere vrouwen in de betreffende landen met elkaar te vergelijken

Het Euro-Peristat-project

Op 11 december 2008 is het rapport verschenen over het Euro-Peristat-project (Peristat-II) waarin perinatale gegevens uit het jaar 2004 op Europees niveau werden vergeleken. Vijfentwintig Europese lidstaten en Noorwegen hebben deelgenomen aan dit grootschalige monitoringsproject. Een van de belangrijkste bevindingen is de hoge perinatale sterfte in Nederland vergeleken met de rest van Europa, zoals beschreven in een overzichtsartikel in het Nederlandse Tijdschrift voor Geneeskunde. Dit project is het vervolg op Peristat-I uit 2003 waaraan vijftien Europese lidstaten hebben deelgenomen. Hiervan werden de resultaten gepubliceerd in een speciale editie van de European Journal of Obstetrics and Gynaecology and Reproductive Biology. In dit hoofdstuk beschrijven wij de opzet en uitvoering van het Euro-Peristat-project en specifiek de Nederlandse gegevensverzameling. Daarnaast geven wij aan welke perinatale indicatoren in de deelnemende landen en in Nederland in het bijzonder beschikbaar zijn

Beschouwing

Vijf jaar na de publicatie van de Peristat-I-studie zijn nu de resultaten van Peristat-II bekend. Vanwege het feit dat Nederland in Peristat-I de hoogste perinatale sterfte had van alle vijftien deelnemende landen, ging de belang- stelling in de tweede ronde uiteraard ook vooral weer uit naar de sterfte rond de geboorte. Voordat de eerste analyses waren uitgevoerd, heerste nog het gevoel dat we deze keer wellicht meer in de middenmoot zouden uitkomen, met zo veel nieuwe deelnemers uit Oost- Europa. Het tweede onderzoek ging immers over 26 landen. Dat gevoel verdween snel toen de preliminaire resultaten verschenen. Ook in Peristat-II staat Nederland niet in de middenmoot, maar in de hogere regionen in negatieve zin. We kunnen nu niet meer hopen dat de resultaten op toevalsbevindingen berusten en dus niets zeggen over de werkelijkheid van de gezondheid van onze zwangere vrouwen en baby’s en de effecten van ons beleid en onze zorg. Zoals in dit tijdschrift al is gezegd: Peristat-II heeft ons bescheidenheid geleerd