Static outliers for Cornbrook 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 Cornbrook Medical Practice is higher than most

BNF Chemical Chemical Items BNF Subparagraph Subparagraph Items Ratio Mean std Z_Score Plots
Arachis oil 6 Shampoos and some other scalp preparations 191 0.03 0.00 0.00 18.13
Mycophenolic sodium 10 Antiproliferative immunosuppressants 44 0.23 0.01 0.03 8.56
Tropicamide 5 Mydriatics and cycloplegics 5 1.00 0.02 0.12 8.44
Estradiol valerate 102 Oestrogens and Hormone Replacement Therapy 281 0.36 0.03 0.04 8.26
Hepatitis A/typhoid vaccine 6 Vaccines and antisera 19 0.32 0.01 0.04 7.64

Prescribing where Cornbrook Medical Practice is lower than most

BNF Chemical Chemical Items BNF Subparagraph Subparagraph Items Ratio Mean std Z_Score Plots
Colecalciferol 605 Vitamin D 714 0.85 0.96 0.02 -4.68
Colecalciferol 400unit / Calcium carbonate 1.5g chewable tab : 105
Adcal-D3 chewable tablets tutti frutti : 154
Adcal-D3 750mg/200unit caplets : 33
Calcichew D3 Forte chewable tablets : 97
Hux D3 20,000unit capsules : 58
Colecalciferol 1,000unit tablets : 2
Colecalciferol 200units/drop oral drops : 2
Colecalciferol 50,000unit tablets : 1
Thorens 10,000units/ml oral drops : 1
Calci-D 1000mg/1,000unit chewable tablets : 1
Colecalciferol 800unit capsules : 14
Colecalciferol 800unit tablets : 14
Colecalciferol 3,000unit tablets : 8
Adcal-D3 Lemon chewable tablets : 8
Colecalciferol 400unit / Calcium carbonate 1.25g chew tab : 26
Colecalciferol 20,000unit capsules : 7
Colecalciferol 5,000unit capsules : 7
Adcal-D3 Dissolve 1500mg/400unit effervescent tablets : 11
Colecalciferol 20,000unit tablets : 6
Colecalciferol 4,000unit tablets : 6
Colecalciferol 400unit tablets : 15
Calcichew D3 chewable tablets : 5
Calcichew D3 1000mg/800unit Once Daily chewable tablets : 5
Calceos 500mg/400unit chewable tablets : 19
Tamsulosin hydrochloride 196 Drugs for urinary retention 269 0.73 0.92 0.06 -3.12
Calcipotriol 73 Preparations for psoriasis 104 0.70 0.87 0.08 -2.05
Lidocaine hydrochloride 23 Local anaesthetics 37 0.62 0.91 0.14 -2.05
Finasteride 135 Male sex hormones and antagonists 226 0.60 0.82 0.12 -1.92