Static outliers for Hillcrest Surgery

There is substantial variation in prescribing behaviours, across various different areas of medicine. Some variation can be explained by demographic changes, or local policies or guidelines, but much of the remaining variation is less easy to explain. At OpenPrescribing we are piloting a number of data-driven approaches to identify unusual prescribing and collect feedback on this prescribing to inform development of new tools to support prescribers and organisations to audit and review prescribing.

This report has been developed to automatically identify prescribing patterns at a chemical level which are furthest away from “typical prescribing” and can be classified as an “outlier”. We calculate the number of prescriptions for each chemical in the BNF coding system using the BNF subparagraph as a denominator, for prescriptions dispensed between April 2021 and August 2021. We then calculate the mean and standard deviation for each numerator and denominator pair across all practices/CCGs/PCNs/STPs. From this we can calculate the “z-score”, which is a measure of how many standard deviations a given practice/CCG/PCN/STP is from the population mean. We then rank your “z-scores” to find the top 5 results where prescribing is an outlier for prescribing higher than its peers and those where it is an outlier for prescribing lower than its peers.

It is important to remember that this information was generated automatically and it is therefore likely that some of the behaviour is warranted. This report seeks only to collect information about where this variation may be warranted and where it might not. Our full analytical method code is openly available on GitHub here.

The DataLab is keen to hear your feedback on the results. You can do this by completing the following survey or emailing us at ebmdatalab@phc.ox.ac.uk. Please DO NOT INCLUDE IDENTIFIABLE PATIENT information in your feedback. All feedback is helpful, you can send short or detailed feedback.

Prescribing where Hillcrest Surgery is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score
Low protein snacks	10	Foods for special diets	244	0.04	0.0	0.00	16.52
Promin low protein Snax salt & vinegar 25g sachets : 1 Promin low protein Snax ready salted 25g sachets : 4 Promin low protein Snax cheese & onion 25g sachets : 5
Chloral hydrate	4	Hypnotics	48	0.08	0.0	0.01	12.33
Chloral hydrate 500mg/5ml oral solution/mixture BP 2000 : 4
Low protein biscuits	25	Foods for special diets	244	0.10	0.0	0.02	6.05
Loprofin low protein cream wafers : 1 Taranis low protein raspberry shortbread biscuits : 4 Mevalia low protein chocotino bars : 3 Vitaflo Choices mini crackers : 7 Taranis low protein chocolate chip cookies : 5 Taranis low protein chocolate chip biscuits : 5
Telmisartan with diuretic	19	Angiotensin-II receptor antagonists	914	0.02	0.0	0.00	4.88
Telmisartan 40mg / Hydrochlorothiazide 12.5mg tablets : 2 Telmisartan 80mg / Hydrochlorothiazide 12.5mg tablets : 12 MicardisPlus 40mg/12.5mg tablets : 5
Rivastigmine	5	Drugs for dementia	9	0.56	0.1	0.10	4.46
Rivastigmine 9.5mg/24hours transdermal patches : 5

Prescribing where Hillcrest Surgery is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score
Ivermectin	0	Topical preparation for rosacea	1	0.00	0.88	0.24	-3.72

Ciprofloxacin	6	Quinolones	12	0.50	0.86	0.15	-2.41
Ciprofloxacin 250mg tablets : 2 Ciprofloxacin 500mg tablets : 4
Methylphenidate hydrochloride	3	CNS Stimulants and drugs used for ADHD	18	0.17	0.65	0.21	-2.35
Concerta XL 27mg tablets : 3
Warfarin sodium	2	Oral anticoagulants	432	0.00	0.24	0.11	-2.15
Warfarin 1mg tablets : 2
Memantine hydrochloride	0	Drugs for dementia	9	0.00	0.37	0.18	-2.09