Qualifications and Experience

I was appointed lecturer in 2000. Previously I had worked as an assistant statistician for the Central Statistical Office of the government of Swaziland. I obtained a BA (1993) from the University of Swaziland, BSc (Hons.) (1997), MSc in Mathematical Statistics (1999) (Modelling relationships between clinical markers of the HIV disease in a South African Population) and Ph.D. in Statistical Sciences (2009) (A variance shift model for outlier detection and estimation in linear and linear mixed models) from the University of Cape Town.

I have taught several under-graduate courses and some post-graduate courses offered by the department. I am currently a Student Advisor in the department for the academic year 2010.  I am a member of the International Biometric Society and the South African Statistical Association, and currently the National Secretary of the South Africa Group of the International Biometric Society. I am a statistical reviewer for the South African Medical Journal and Biomed Central (BMC) Journal Series. In 2005, I was awarded a one-year Commonwealth Scholarship to work on my PhD at Rothamsted Research, UK, under the supervision of Dr. Sue Welham and Prof. Robin Thompson.

I served on the South African Medical Association Journal Editorial Advisory Committee during the period June 2002 - January 2003. I am a member of the International Biometrics Society and National Secretary National Secretary of the South Africa Group (GSAF) of the International Biometric Society. As a student, I was sub-warden of Groote Schuur Residence of UCT in 1999 and was also a member of the UCT’s Student Parliament in 1997.

Research Interests

My research interests lie in the development and application of statistical methods in health research and education. My specific statistical research areas include longitudinal data analysis, generalized linear models, generalized linear mixed models, mixed models (detection and accommodation of outliers), survival analysis, clinical trials, Bayesian statistics and statistical consulting. I collaborate with researchers in cardiology, dermatology, education and HIV-AIDS.

Projects Available

The following projects are available to honours and MSc students.

• A variance shift outlier model (VSOM) for correlated data. This project will develop and evaluate the VSOM for innovative outliers for AR-type models (Auto-Regressive and ante-dependence).

• A variance shift outlier model for the detection and accommodation of outlying subjects in random coefficient regression.

Publications (since 2007)

• Gumedze, F. , and T.T. Dunne. (2011). Parameter estimation and inference in the linear mixed model. Linear Algebra and its Applications, 435, 1920-1944.

• Gumedze, F. , and Jackson, D. (2011). A random effects variance shift model for detecting and accommodating outliers in meta-analysis. BMC Medical Research Methodology, 11, 1-19.

• Ntusi, N.B.A, Badri, M., Gumedze, F., McGrath E., Ngwanya L. Wonkam, A. and Mayosi, B. (2011). Clinical characteristics and outcome of familial and idiopathic dilated cardiomyopathy in South Africa: implications for clinical practice and research.   South African Medical Journal, 101 (6), 399-404.

• Gumedze, F. N., Welham, S. J., Gogel, B.J. and Thompson, R. (2010). A variance shift model for detection of outliers in the linear mixed model. Journal of Computational Statistics and Data Analysis, 54 (9), 2128-2144.

• Khumalo, N.P., Stone J., Gumedze, F., McGrath E., Ngwanya L. and De Berker, D. (2010). ‘Relaxers’ damage hair: Evidence from amino acid analysis.  Journal of the American Academy of Dermatology, 62 (3), 402-408.

• Khumalo, N.P., Jessop, S., Gumedze, F. and Ehrlich, R. (2008). Determinants of marginal traction alopecia in African girls and women. Journal of the American Academy of Dermatology, 59 (3), 432-438.

• Mayosi, B.M., Wiysonge, C.S., Ntsekhe, M., Volmink, J.M., Gumedze, F., Maartens, G., Aje, A., Thomas, B.M., Thomas, K.M., Awotedu, A.A., Thembela, B., Mntla, P., Maritz, F. [Late], Blackett, K.N., Nkouonlack, D.C., Burch, V.C.,Rebe, K., Parish, A., Sliwa, K., Vezi, B.Z., Alam, N., Brown, B.G., Gould, T., Visser, T., Magula, N.P. and Commerford, P.J. (2008). Mortality in patients treated for tuberculous pericarditis in sub-Saharan Africa. South African Medical Journal, 98 (1), 29-36.

• Ntsekhe, M, Wiysonge, C.S., Gumedze, F., Maartens, G., Commerford, P.J. Volmink, J.A. and Mayosi, B.M. (2008). HIV infection is associated with a lower incidence of constriction in presumed tuberculous pericarditis: a prospective observational study PLoS ONE, 3 (6): e2253. doi:10.1371/journal.pone.0002253.

• Wiysonge, C.S., Ntsekhe, Gumedze, F., Sliwa, K., Blackett, K.N.,  Commerford, P., Volmink, J.A. and Mayosi, B.M. (2008). Contemporary use of adjunctive corticosteroids in the management of tuberculous pericarditis in Africa: evidence of clinical equipoise. International Journal of Cardiology, 124, 388-390.

• Khumalo, N.P., Ehrlich, R. and Gumedze, F. (2007). Hairstyling is associated with scalp disease in African schoolchildren. British Journal of Dermatology, 157 (1), 106-110.

• Khumalo, N.P. and Gumedze, F. (2007). African hair length in a school population: a clue to disease pathogenesis. Journal of Cosmetic Dermatology, 6 (3), 144-151.

• Khumalo, N.P., Jessop, S., Gumedze, F. and Ehrlich, R. (2007). Hairdressing and the prevalence of scalp disease in African adults. British Journal of Dermatology, 157 (5), 981-988.

• Khumalo, N.P., Jessop, S., Gumedze, F. and Ehrlich, R. (2007). Marginal Traction Alopecia Severity Score – development and test reliability. Journal of Cosmetic Dermatology, 6 (4), 262-269.