TY  - JOUR
A1  - Mühlenbruch, Kristin
A1  - Zhuo, Xiaohui
A1  - Bardenheier, Barbara
A1  - Shao, Hui
A1  - Laxy, Michael
A1  - Icks, Andrea
A1  - Zhang, Ping
A1  - Gregg, Edward W.
A1  - Schulze, Matthias Bernd
T1  - Selecting the optimal risk threshold of diabetes risk scores to identify high-risk individuals for diabetes prevention
BT  - a cost-effectiveness analysis
JF  - Acta Diabetologica
N2  - Aims:
Although risk scores to predict type 2 diabetes exist, cost-effectiveness of risk thresholds to target prevention interventions are unknown. We applied cost-effectiveness analysis to identify optimal thresholds of predicted risk to target a low-cost community-based intervention in the USA. 

Methods:
We used a validated Markov-based type 2 diabetes simulation model to evaluate the lifetime cost-effectiveness of alternative thresholds of diabetes risk. Population characteristics for the model were obtained from NHANES 2001-2004 and incidence rates and performance of two noninvasive diabetes risk scores (German diabetes risk score, GDRS, and ARIC 2009 score) were determined in the ARIC and Cardiovascular Health Study (CHS). Incremental cost-effectiveness ratios (ICERs) were calculated for increasing risk score thresholds. Two scenarios were assumed: 1-stage (risk score only) and 2-stage (risk score plus fasting plasma glucose (FPG) test (threshold 100 mg/dl) in the high-risk group). 

Results:
In ARIC and CHS combined, the area under the receiver operating characteristic curve for the GDRS and the ARIC 2009 score were 0.691 (0.677-0.704) and 0.720 (0.707-0.732), respectively. The optimal threshold of predicted diabetes risk (ICER < $50,000/QALY gained in case of intervention in those above the threshold) was 7% for the GDRS and 9% for the ARIC 2009 score. In the 2-stage scenario, ICERs for all cutoffs >= 5% were below $50,000/QALY gained.

Conclusions:
Intervening in those with >= 7% diabetes risk based on the GDRS or >= 9% on the ARIC 2009 score would be cost-effective. A risk score threshold >= 5% together with elevated FPG would also allow targeting interventions cost-effectively.
KW  - diabetes mellitus
KW  - type 2
KW  - cost-effectiveness analysis
KW  - lifestyle risk reduction
KW  - clinical prediction rule
Y1  - 2019
U6  - https://doi.org/10.1007/s00592-019-01451-1
SN  - 0001-5563
SN  - 0940-5429
SN  - 1432-5233
VL  - 57
IS  - 4
SP  - 447
EP  - 454
PB  - Springer
CY  - Mailand
ER  - 
TY  - JOUR
A1  - Mühlenbruch, Kristin
A1  - Kuxhaus, Olga
A1  - Pencina, Michael J.
A1  - Boeing, Heiner
A1  - Liero, Hannelore
A1  - Schulze, Matthias Bernd
T1  - A confidence ellipse for the Net Reclassification Improvement
JF  - European journal of epidemiology
N2  - The Net Reclassification Improvement (NRI) has become a popular metric for evaluating improvement in disease prediction models through the past years. The concept is relatively straightforward but usage and interpretation has been different across studies. While no thresholds exist for evaluating the degree of improvement, many studies have relied solely on the significance of the NRI estimate. However, recent studies recommend that statistical testing with the NRI should be avoided. We propose using confidence ellipses around the estimated values of event and non-event NRIs which might provide the best measure of variability around the point estimates. Our developments are illustrated using practical examples from EPIC-Potsdam study.
KW  - Risk assessment
KW  - Risk model
KW  - Model comparison
KW  - Reclassification
KW  - Confidence intervals
Y1  - 2015
U6  - https://doi.org/10.1007/s10654-015-0001-1
SN  - 0393-2990
SN  - 1573-7284
VL  - 30
IS  - 4
SP  - 299
EP  - 304
PB  - Springer
CY  - Dordrecht
ER  - 
TY  - THES
A1  - Mühlenbruch, Kristin
T1  - Updating the german diabetes risk score - model extensions, validation and reclassification
Y1  - 2013
CY  - Potsdam
ER  -