Static outliers for The Ridgeway 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 The Ridgeway Surgery is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score
Ertugliflozin	159	Other antidiabetic drugs	2862	0.06	0.0	0.00	16.36
Ertugliflozin 5mg tablets : 151 Ertugliflozin 15mg tablets : 8
Other mouth wash, gargle and dentifrice preparations	6	Mouth-washes, gargles and dentifrices	20	0.30	0.0	0.03	10.49
UltraDEX Oral Rinse : 6
Wool alcohols	29	Emollients	470	0.06	0.0	0.01	5.86
Hydrous ointment : 29
Low protein cooking aids	4	Foods for special diets	199	0.02	0.0	0.00	5.62
Loprofin low protein egg replacer : 4
Pentosan polysulfate sodium	4	Oral anticoagulants	2008	0.00	0.0	0.00	4.97
Elmiron 100mg capsules (Consilient Health) : 4

Prescribing where The Ridgeway Surgery is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score
Chlorhexidine gluconate	12	Mouth-washes, gargles and dentifrices	20	0.60	0.97	0.11	-3.55
Chlorhexidine gluconate 0.2% mouthwash : 9 Corsodyl 0.2% mouthwash aniseed : 3
Amitriptyline hydrochloride	691	Tricyclic and related antidepressant drugs	1024	0.67	0.84	0.08	-2.16
Amitriptyline 10mg tablets : 575 Amitriptyline 25mg tablets : 70 Amitriptyline 50mg tablets : 46
Quinine sulfate	109	Antimalarials	183	0.60	0.89	0.14	-2.10
Quinine sulfate 200mg tablets : 38 Quinine sulfate 300mg tablets : 71
Other multivitamin preparations	76	Multivitamin preparations	198	0.38	0.81	0.21	-2.05
Renavit tablets : 33 Abidec Multivitamin drops : 9 Forceval capsules : 24 Dalivit oral drops : 5 Forceval Soluble tablets : 5
Rifampicin	0	Antituberculosis drugs	5	0.00	0.73	0.40	-1.81