Static outliers for Ribblesdale Medical Practice

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 Ribblesdale Medical Practice is higher than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score
Cloral betaine	1	Hypnotics	243	0.00	0.00	0.00	14.25
Cloral betaine 707mg tablets : 1
Isometheptene mucate	4	Non-opioid analgesics and compound preparations	2204	0.00	0.00	0.00	9.77
Midrid 325mg/65mg capsules : 4
Flupentixol hydrochloride	27	Antipsychotic drugs	453	0.06	0.00	0.01	6.67
Flupentixol 3mg tablets : 16 Depixol 3mg tablets : 11
Acenocoumarol	18	Oral anticoagulants	1089	0.02	0.00	0.00	5.04
Sinthrome 1mg tablets : 18
Promazine hydrochloride	84	Antipsychotic drugs	453	0.19	0.01	0.04	4.65
Promazine 25mg/5ml oral solution : 61 Promazine 50mg/5ml oral solution : 13 Promazine 50mg tablets : 3 Promazine 25mg tablets : 7

Prescribing where Ribblesdale Medical Practice is lower than most

BNF Chemical	Chemical Items	BNF Subparagraph	Subparagraph Items	Ratio	Mean	std	Z_Score
Folic acid	220	Drugs used in megaloblastic anaemias	803	0.27	0.70	0.16	-2.68
Folic acid 5mg tablets : 209 Folic acid 2.5mg/5ml oral solution sugar free : 2 Folic acid 400microgram tablets : 9
Amlodipine	1224	Calcium-channel blockers	2518	0.49	0.75	0.11	-2.37
Amlodipine 5mg tablets : 760 Amlodipine 10mg tablets : 464
Carbimazole	14	Antithyroid drugs	20	0.70	0.93	0.11	-2.18
Carbimazole 20mg tablets : 3 Carbimazole 5mg tablets : 11
Methylprednisolone acetate	0	Local corticosteroid injections	62	0.00	0.73	0.39	-1.87

Sodium chloride	0	Topical nasal decongestants	18	0.00	0.54	0.31	-1.72