Professor Karla Hemming PhD

Professor Karla Hemming

Institute of Applied Health Research
Professor of Biostatistics

Contact details

Public Health, Epidemiology and Biostatistics
Institute of Applied Health Research
College of Medical and Dental Sciences
University of Birmingham
Birmingham, B15 2TT

Karla Hemming leads a research programme related to stepped wedge trials, this includes both theoretical and applied research. Karla has close links with the West Midlands CLAHRC (Collaborations for Leadership in Applied Health Research and Care) and through this collaboration has helped establish and complete three stepped-wedge studies. Karla is affiliated with the Birmingham Clinical Trials Unit (BCTU) and provides methodological support for the design of cluster and stepped wedge trials. Karla is known internationally as an expert in stepped-wedge trials, has been invited to speak at international conferences, sits on international data monitoring committees and receives frequent requests for advise on stepped wedge trials from around the world.

Karla sits on the NIHR program grants panel, the West Midlands Research for patient benefit funding panel; and is a statistical editor for the BJOG. 


Postgraduate supervision

Karla Hemming's research interests include perinatal epidemiology, meta-analysis, missing data and cluster trials. She has conducted and published research in a number of areas, including:

Prescribing errors in electronic prescribing
Large-scale organisational intervention to improve patient safety
Bayesian sensitivity models for missing covariates in the analysis of survival data
Meta-regression with partial information


Recent publications


Daniels, J, Dixon, EF, Gill, A, Bishop, J, D’Amico, M, Ahmed, K, Dodds, J, Tryposkiadis, K, Wilks, M, Millar, M, Husain, S, Gray, J, Whiley, A, Moore, PV, Munetsi, RL, Hemming, K, Roberts, T, Plumb, J, Deeks, J, Khan, KS & Thangaratinam, S 2022, 'A rapid intrapartum test for group B Streptococcus to reduce antibiotic usage in mothers with risk factors: the GBS2 cluster RCT', Health Technology Assessment, vol. 26, no. 12, pp. vii-76.

Hemming, K, Javid, I & Taljaard, M 2022, 'A review of high impact journals found that misinterpretation of non-statistically significant results from randomized trials was common', Journal of Clinical Epidemiology, vol. 145, pp. 112-120.

Bick, D, Bishop, J, Coleman, T, Dean, S, Edwards, E, Frawley, H, Gkini, E, Hay-Smith, J, Hemming, K, Jones, E, Oborn, E, Pearson, M, Salmon, V, Webb, S & MacArthur, C 2022, 'Antenatal preventative pelvic floor muscle exercise intervention led by midwives to reduce postnatal urinary incontinence (APPEAL): protocol for a feasibility and pilot cluster randomised controlled trial', Pilot and Feasibility Studies, vol. 8, no. 1, pp. 231.

Blackwood, B, Morris, KP, Jordan, J, McIlmurray, L, Agus, A, Boyle, R, Clarke, M, Easter, C, Feltbower, RG, Hemming, K, Macrae, D, McDowell, C, Murray, M, Parslow, R, Peters, MJ, Phair, G, Tume, LN, Walsh, TS & McAuley, DF 2022, 'Co-ordinated multidisciplinary intervention to reduce time to successful extubation for children on mechanical ventilation: the SANDWICH cluster stepped-wedge RCT', Health Technology Assessment, vol. 26, no. 18, pp. 1-114.

Hemming, K & Taljaard, M 2022, 'Estimands in cluster trials: thinking carefully about the target of inference and the consequences for analysis choice', International Journal of Epidemiology, pp. 1-3.

Kristunas, C, Grayling, M, Gray, LJ & Hemming, K 2022, 'Mind the gap: covariate constrained randomisation can protect against substantial power loss in parallel cluster randomised trials', BMC Medical Research Methodology, vol. 22, no. 1, 111.

Osuh, ME, Oke, GA, Lilford, RJ, Owoaje, E, Harris, B, Taiwo, OJ, Yeboah, G, Abiona, T, Watson, SI, Hemming, K, Quinn, L, Chen, Y & Trevisan, M (ed.) 2022, 'Prevalence and determinants of oral health conditions and treatment needs among slum and non-slum urban residents: evidence from Nigeria', PLOS Global Public Health, vol. 2, no. 4, e0000297.

Kudhail, K, Thompson, J, Mathews, V, Morrison, B & Hemming, K 2022, 'Randomized controlled trials in patients with COVID-19: a systematic review and critical appraisal', International Journal of Infectious Diseases, vol. 122, pp. 72-80.

GBS2 Collaborative Group 2022, 'Rapid intrapartum test for maternal group B streptococcal colonisation and its effect on antibiotic use in labouring women with risk factors for early-onset neonatal infection (GBS2): cluster randomised trial with nested test accuracy study', BMC Medicine, vol. 20, no. 1, 9.

Kudrna, L, Bird, P, Hemming, K, Quinn, L, Schmidtke, K & Lilford, R 2022, 'Retrospective evaluation of an intervention based on training sessions to increase the use of control charts in hospitals', BMJ Quality & Safety.

Sheppard, D, Clarke, E, Hemming, K, Martin, J & Lilford, R 2021, 'An opportunistic evaluation of a routine service improvement project to reduce falls in hospital', BMC Health Services Research, vol. 21, no. 1, 79.

CRT Binary Outcome Reporting Group 2021, 'Completeness of reporting and risks of overstating impact in cluster randomised trials: a systematic review', Lancet Global Health, vol. 9, no. 8, pp. e1163-e1168.

Hemming, K, Taljaard, M, Moerbeek, M & Forbes, A 2021, 'Contamination: How much can an individually randomized trial tolerate?', Statistics in Medicine, vol. 40, no. 14, pp. 3329-3351.

Review article

Quinn, L, Veenith, T, Bion, J, Hemming, K, Whitehouse, T & Lilford, R 2022, 'Bayesian analysis of a systematic review of early versus late tracheostomy in ICU patients', British Journal of Anaesthesia, vol. 129, no. 5, pp. 693-702.

Easter, C, Thompson, JA, Eldridge, S, Taljaard, M & Hemming, K 2021, 'Cluster randomized trials of individual-level interventions were at high risk of bias', Journal of Clinical Epidemiology, vol. 138, pp. 49-59.

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