A mathematical model for designing networks of C-Reactive Protein point of care testing

Abstract

One approach to improving antibiotic stewardship in primary care may be to support all General Practitioners (GPs) to have access to point of care C-Reactive Protein tests to guide their prescribing decisions in patients presenting with symptoms of lower respiratory tract infection. However, to date there has been no work to understand how clinical commissioning groups might approach the practicalities of system-wide implementation. We aimed to develop an accessible service delivery modelling tool that, based on open data, could generate a layout of the geographical distribution of point of care facilities that minimised the cost and travel distance for patients across a given region. We considered different implementation models where point of care tests were placed at either GP surgeries, pharmacies or both. We analysed the trade-offs between cost and travel found by running the model under different configurations and analysing the model results in four regions of England (two urban, two rural). Our model suggests that even under assumptions of short travel distances for patients (e.g. under 500m), it is possible to achieve a meaningful reduction in the number of necessary point of care testing facilities to serve a region by referring some patients to be tested at nearby GP surgeries or pharmacies. In our test cases pharmacy-led implementation models resulted in some patients having to travel long distances to obtain a test, beyond the desired travel limits. These results indicate that an efficient implementation strategy for point of care tests over a geographic region, potentially building on primary care networks, might lead to significant cost reduction in equipment and associated personnel training, maintenance and quality control costs; as well as achieving fair access to testing facilities.

Respiratory tract infections (RTIs) in primary care: narrative review of C reactive protein (CRP) point-of-care testing (POCT) and antibacterial use in patients who present with symptoms of RTI

“…A mathematical model for designing networks of CRP POCT could optimise the cost and travel distance for patients to access testing across a given region. 57 …”

“…56 A mathematical model for designing networks of CRP POCT could optimise the cost and travel distance for patients to access testing across a given region. 57 A mixed-methods UK study with CRP POCT confirmed costs and funding as important barriers in addition to physical and operational constraints and cited training and the value of a local champion as enablers. 58 In a US study to ascertain which POCTs would be most beneficial to add to clinical practice, incorporating CRP POCT with clinical guidelines was felt to strengthen the utility of this test, when there is diagnostic uncertainty.…”

Use of Physical Accessibility Modelling in Diagnostic Network Optimization: A Review

“…Three types of geographic accessibility measures were identified: those using travel time [ 8 , 19 ], those using distance [ 20 , 21 , 22 , 23 ], and one combining these two measures [ 18 ]. The studies used different strategies to measure physical accessibility: using ArcGIS Costdistance function (ESRI, Redlands, CA, USA), for a unique transport mode and a mean travel speed [ 18 ]; using ArcGIS ModelBuilder to solve a Vehicle Routing Problem, considering several transport modes and speeds [ 19 ], or only a single transport mode [ 8 ]; using the Open-Source Routing Machine to compute walking distance [ 23 ]; using distance data along transport routes where known, otherwise using a distance adjustment factor to define them [ 20 , 22 ]; and finally, using Euclidean distances to determine the coverage of a health center [ 21 ].…”

“…For studies looking at specimen referrals, one includes all levels of health centers in their analysis [ 20 ], others link specimens from all types of health facilities to centralized laboratories [ 19 , 21 ], one focuses on the transport of specimens between Point-of-Care and centralized laboratories [ 8 ], while the latter is concerned with referrals from community centers to general hospitals [ 22 ]. The publication involving patient travel implies patient reference from their usual General Practitioner to another GP location or to pharmacies [ 23 ].…”

“…Several publications propose a motorbike as a mode of transport [ 8 , 18 , 20 ]. Two studies include several modes of transport [ 19 , 22 ], one only includes walking [ 23 ], and the last one does not include any specified mode of transport [ 21 ].…”