Static outliers for Cranham Health Centre

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 Cranham Health Centre is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Tafluprost and timolol☰	26	Treatment of glaucoma	443	0.06	0.00	0.01	7.19
Taptiqom 15micrograms/ml / 5mg/ml eye drops 0.3ml unit dose : 21 Tafluprost 15microg/Timolol 5mg/ml eye dps 0.3ml : 5
Aspirin☰	16	Non-opioid analgesics and compound preparations	850	0.02	0.00	0.00	6.64
Aspirin 300mg dispersible tablets : 16
Liquid paraffin☰	22	Tear deficiency, eye lubricant/astringent	189	0.12	0.01	0.02	6.23
Lacri-lube eye ointment : 22
Azelastine hydrochloride☰	12	Other anti-inflammatory preparations	24	0.50	0.06	0.08	5.69
Azelastine 0.05% eye drops : 12
Apomorphine hydrochloride☰	8	Dopaminergic drugs used in parkinsonism	163	0.05	0.00	0.01	5.27
APO-go PEN 30mg/3ml solution for injection : 2 APO-go PFS 50mg/10ml inf pre-filled syringes : 6

Prescribing where Cranham Health Centre is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Calcipotriol☰	20	Preparations for psoriasis	36	0.56	0.87	0.08	-3.82
Dovobet ointment : 8 Enstilar 50micrograms/g / 0.5 mg/g cutaneous foam : 7 Dovonex 50micrograms/g ointment : 5
Sodium cromoglicate☰	3	Other anti-inflammatory preparations	24	0.12	0.67	0.18	-2.97
Sodium cromoglicate 2% eye dps 0.3ml ud preservative free : 2 Sodium cromoglicate 2% eye drops : 1
Clotrimazole☰	12	Vaginal and vulval infections	19	0.63	0.90	0.10	-2.79
Clotrimazole 500mg pessaries : 2 Clotrimazole 10% vaginal cream : 2 Clotrimazole 200mg pessaries : 4 Clotrimazole 2% cream : 4
Levothyroxine sodium☰	1306	Thyroid hormones	1318	0.99	1.00	0.00	-2.58
Levothyroxine sodium 25microgram tablets : 421 Levothyroxine sodium 50microgram tablets : 466 Levothyroxine sodium 100microgram tablets : 414 Levothyroxine sodium 75microgram tablets : 2 Levothyroxine sodium 50micrograms/5ml soln sugar free : 3
Pizotifen malate☰	2	Prophylaxis of migraine	34	0.06	0.65	0.26	-2.27
Pizotifen 500microgram tablets : 2