Static outliers for The James Cochrane Pract.

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 The James Cochrane Pract. is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Isotretinoin☰	116	Oral preparations for acne	126	0.92	0.03	0.13	6.63
Isotretinoin 20mg capsules : 88 Isotretinoin 5mg capsules : 2 Isotretinoin 10mg capsules : 26
Magnesium oxide☰	10	Antacids and simeticone	10	1.00	0.05	0.19	5.07
Magnesium oxide 160mg capsules : 10
Benzalkonium chloride☰	3	Barrier preparations	4	0.75	0.05	0.14	4.93
Drapolene cream : 3
Lixisenatide☰	16	Other antidiabetic drugs	615	0.03	0.00	0.01	3.89
Lixisenatide 20micrograms/0.2ml inj 3ml pf dispos dev : 16
Methenamine hippurate☰	146	Urinary-tract infections	577	0.25	0.03	0.06	3.61
Methenamine hippurate 1g tablets : 131 Hiprex 1g tablets : 15

Prescribing where The James Cochrane Pract. is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score	Plots
Co-cyprindiol (Cyprote acetate/ethinylestradiol)☰	10	Oral preparations for acne	126	0.08	0.97	0.13	-6.63
Co-cyprindiol 2000microgram/35microgram tablets : 10
Nitrofurantoin☰	431	Urinary-tract infections	577	0.75	0.97	0.06	-3.60
Nitrofurantoin 100mg modified-release capsules : 398 Nitrofurantoin 50mg tablets : 3 Nitrofurantoin 50mg capsules : 20 Nitrofurantoin 100mg tablets : 10
Trimethoprim☰	50	Sulfonamides and trimethoprim	90	0.56	0.86	0.13	-2.39
Trimethoprim 200mg tablets : 32 Trimethoprim 50mg/5ml oral suspension sugar free : 7 Trimethoprim 100mg tablets : 11
Prucalopride☰	0	Other drugs used in constipation	14	0.00	0.71	0.33	-2.18
Doxycycline hyclate☰	165	Tetracyclines	463	0.36	0.63	0.14	-2.04
Doxycycline 100mg capsules : 165