Neil A Martinson

University of the Witwatersrand, Johannesburg, Gauteng, South Africa

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Publications (108)555.52 Total impact

  • Tuberculosis 05/2015; DOI:10.1016/j.tube.2015.05.006 · 3.50 Impact Factor
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    ABSTRACT: Liver disease epidemiology in sub-Saharan Africa has shifted as a result of HIV and the increased use of antiretroviral therapy leading to a need for updated data on common causes of liver disease. We retrospectively reviewed records from all hospitalized patients who had liver biopsy at a single hospital in South Africa from 2001 to 2009 and compared diagnosis by HIV status. During the period of study 262 patients had liver biopsy, 108 (41%) were HIV-infected, 25 (10%) were HIV-sero-negative, and 129 (49%) had unknown or unrecorded HIV status. Overall 81% of biopsies provided additional diagnostic data. Malignancy was the most common finding reported on 56 (21%) biopsies followed by granuloma or TB, hepatic steatosis, and fibrosis or cirrhosis. HIV-infected patients were more likely to have granulomas and steatosis. Half of patients with granulomas were already on TB treatment, suggesting paradoxical reactions or drug induced liver injury may have been important causes of liver inflammation among these patients. We note that TB, paradoxical reactions during TB treatment, possible drug induced liver injury, and hepatic steatosis are important causes of liver pathology among HIV-infected hospitalized patients with unclear etiology of liver disease after initial assessment. Among HIV sero-negative patients, malignancy was the major cause of liver disease. Our findings re-enforce the importance of TB as a diagnosis among HIV-infected individuals.
    PLoS ONE 02/2015; 10(2):e0117813. DOI:10.1371/journal.pone.0117813 · 3.53 Impact Factor
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    ABSTRACT: Scaling up services to achieve HIV targets will require that countries optimize the use of available funding. Robust unit cost estimates are essential for the better use of resources, and information on the heterogeneity in the unit cost of delivering HIV services across facilities - both within and across countries - is critical to identifying and addressing inefficiencies. There is limited information on the unit cost of HIV prevention services in sub-Saharan Africa and information on the heterogeneity within and across countries and determinants of this variation is even more scarce. The "Optimizing the Response in Prevention: HIV Efficiency in Africa" (ORPHEA) study aims to add to the empirical body of knowledge on the cost and technical efficiency of HIV prevention services that decision makers can use to inform policy and planning. ORPHEA is a cross-sectional observational study conducted in 304 service delivery sites in Kenya, Rwanda, South Africa, and Zambia to assess the cost, cost structure, cost variability, and the determinants of efficiency for four HIV interventions: HIV testing and counselling (HTC), prevention of mother-to-child transmission (PMTCT), voluntary medical male circumcision (VMMC), and HIV prevention for sex workers. ORPHEA collected information at three levels (district, facility, and individual) on inputs to HIV prevention service production and their prices, outputs produced along the cascade of services, facility-level characteristics and contextual factors, district-level factors likely to influence the performance of facilities as well as the demand for HIV prevention services, and information on process quality for HTC, PMTCT, and VMMC services. ORPHEA is one of the most comprehensive studies on the cost and technical efficiency of HIV prevention interventions to date. The study applied a robust methodological design to collect comparable information to estimate the cost of HTC, PMTCT, VMMC, and sex worker prevention services in Kenya, Rwanda, South Africa, and Zambia, the level of efficiency in the current delivery of these services, and the key determinants of efficiency. The results of the study will be important to decision makers in the study countries as well as those in countries facing similar circumstances and contexts.
    BMC Health Services Research 11/2014; 14(1):599. DOI:10.1186/s12913-014-0599-9 · 1.66 Impact Factor
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    ABSTRACT: INTRODUCTION Evidence on the efficiency of HIV prevention interventions is limited. ORPHEA project aimed to estimate average costs and analyse their heterogeneity for three HIV prevention interventions: prevention of mother-to-child transmission (PMTCT), voluntary medical male-circumcision (VMMC), and HIV-testing and counseling (HTC), in Kenya, Zambia, Rwanda and South-Africa. METHODS Sample comprises of 60-80 clinics per country. Micro-costing was performed and relevant costs (personnel, supplies, utilities, equipment and property) and intervention-output data were collected retrospectively for 2011/2012. Information on time-allocation, building-space-used and time-motion is also collected . Quality is captured by measuring the facility’s attrition rate at each stage along the service delivery, using provider-vignettes and patient-exit-interviews. We estimated average-cost per each HIV prevention intervention. RESULTS Estimated weighted-average costs were US$18.1 per HTC client, US$50.1 per women tested in PMTCT services, US$93.4 per MC client. Staff costs account for more than 80% of the average costs in each prevention intervention. Variation in average cost for HTC and PMTCT by facility type is limited, except for faith-based hospitals. VMMC costs show important variations among different type of facilities, resulting cheaper to perform VMMC intervention in health centres. CONCLUSIONS Results suggest that there is a large potential to increase efficiency within the current financial and structural constraints of the health system in some countries in Africa. Staff accounts for the larger proportion of average-costs and offer the highest potential to implement actions to increase efficiency and quality. There is also need to explore different types of service delivery-models and their impacts on efficiency.
    142nd APHA Annual Meeting and Exposition 2014; 11/2014
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    ABSTRACT: Background: While healthcare services become increasingly available in developing countries, there is heterogeneity in the quality of service delivery across health providers. As part of a cost-efficiency project (ORPHEA) conducted in Kenya, Zambia, South Africa and Rwanda, we assessed the quality of three HIV prevention interventions: Voluntary Medical Male Circumcision (VMMC), Prevention of Mother-to-Child Transmission (PMTCT), and HIV Testing and Counseling (HTC). Description: We used multistage sampling techniques to select 60-80 health facilities per country stratifying by facility location, size and type. We conducted cross-sectional provider vignettes and patient exit interviews (PEI) to assess service quality measures by estimating provider competence and performance scores. Provider competence scores were compared with average scores for provider performance at the facility level to estimate potential performance. Results: Results are currently available for two (Kenya, Zambia) of the four countries*, where we surveyed 799 providers and 1,161 clients. On average, HTC healthcare providers had a vignette score of 59% and a PEI score of 26%; PMTCT providers had a vignette score of 56% and a PEI score of 32%; and VMMC providers had a vignette score of 67% and received a score of 48% from PEI. Conclusions: We found, there is significant opportunity to increase quality of services without additional health resources but rather by reallocating labor resources. There is therefore need to investigate how different service delivery models could be implemented to reach full performance. ------------------------- * Results from the remaining two countries may be available by the time of the conference. Learning Areas: Biostatistics, economics Conduct evaluation related to programs, research, and other areas of practice Provision of health care to the public Public health or related research Social and behavioral sciences Learning Objectives: Assess the quality of three HIV prevention interventions in Kenya, Rwanda, South Africa and Zambia. Keywords: HIV Interventions, Quality of Care Presenting author's disclosure statement: Qualified on the content I am responsible for because: I am a researcher at the Center for Health Systems Research at the Mexico National Institute of Public Health (INSP) where I have been involved in multi-country economic, impact, and efficiency evaluations in in low- and middle-income countries. I hold a master's degree in economics. Any relevant financial relationships? No I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation. Back to: 4330.0: HIV/AIDS in International Settings
    142nd APHA Annual Meeting and Exposition 2014; 11/2014
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    ABSTRACT: Introduction: Staff costs comprise the largest share of average facility costs to provide HIV prevention services. Evidence has shown that greater scale of production reduces average costs of these interventions. Little is known about the optimal combination of staff and quality that predict technical efficiency, as to increase value-for-money of HIV spending. Methods: A cost analysis was implemented at 92 facilities offering HTC in Kenya, Zambia, Rwanda and South Africa in 2011-2012. Staff costs were allocated to interventions using time-motion data. Standardized vignettes were administered to score technical proficiency. We estimated average staff cost by dividing total prorated staff costs by the number of HTC clients in each facility. We created quantiles of operation scale and quality, to analyze its tradeoff and explore costs efficiency of HTC delivery. Results: Mean staff costs per client tested were 18.8 USD (IQR: 0.5;18.1), with heterogeneity by facility type. Independent of health providers' competence score, operation scale negatively correlated with average costs: Moving from the first quartile of scale towards the upper quartile yielded a 90% reduction in staff costs. Among the subset of facilities in the uppermost quartile of scale, we found a mean difference in staff costs between the lower and upper quartiles of providers’ competence of 1.2 USD. Conclusions: These results demonstrate the need to understand the mechanisms that curb efficiency in the provision of HIV prevention interventions. We provide evidence of the possibility to achieve higher quality of care without escalating the budget, provided that service utilization is increased.
    142nd APHA Annual Meeting and Exposition 2014; 11/2014
  • AIDS Research and Human Retroviruses 10/2014; 30 Suppl 1:A197. DOI:10.1089/aid.2014.5425.abstract · 2.46 Impact Factor
  • AIDS Research and Human Retroviruses 10/2014; 30 Suppl 1:A64. DOI:10.1089/aid.2014.5116a.abstract · 2.46 Impact Factor
  • AIDS Research and Human Retroviruses 10/2014; 30 Suppl 1:A219-20. DOI:10.1089/aid.2014.5478.abstract · 2.46 Impact Factor
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    ABSTRACT: Background: Factors associated with mortality in HIV-infected people in sub-Saharan Africa are widely reported. However rural-urban disparities and their association with all-cause mortality remain unclear. Furthermore, commonly used classical Cox regression ignores unmeasured variables and frailty. Objective: To incorporate frailty in assessing factors associated with mortality in HIV-infected people in rural and urban South Africa. Design: Using data from a prospective cohort following 6,690 HIV-infected participants from Soweto (urban) and Mpumalanga (rural) enrolled from 2003 to 2010; covariates of mortality were assessed by the integrated nested Laplace approximation method. Results: We enrolled 2,221 (33%) rural and 4,469 (67%) urban participants of whom 1,555 (70%) and 3,480 (78%) were females respectively. Median age (IQR) was 36.4 (31.0-44.1) in rural and 32.7 (28.2-38.1) in the urban participants. The mortality rate per 100 person-years was 11 (9.7-12.5) and 4 (3.6-4.5) in the rural and urban participants, respectively. Compared to those not on HAART, rural participants had a reduced risk of mortality if on HAART for 6-12 (HR: 0.20, 95% CI: 0.10-0.39) and >12 months (HR: 0.10, 95% CI: 0.05-0.18). Relative to those not on HAART, urban participants had a lower risk if on HAART >12 months (HR: 0.35, 95% CI: 0.27-0.46). The frailty variance was significant and >1 in rural participants indicating more heterogeneity. Similarly it was significant but <1 in the urban participants indicating less heterogeneity. Conclusion: The frailty model findings suggest an elevated risk of mortality in rural participants relative to the urban participants potentially due to unmeasured variables that could be biological, socio-economic, or healthcare related. Use of robust methods that optimise data and account for unmeasured variables could be helpful in assessing the effect of unknown risk factors thus improving patient management and care in South Africa and elsewhere.
    Global Health Action 09/2014; 7:25488. DOI:10.3402/gha.v7.25488 · 1.65 Impact Factor
  • The International Journal of Tuberculosis and Lung Disease 08/2014; 18(8). DOI:10.5588/ijtld.13.0855 · 2.76 Impact Factor
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    ABSTRACT: Background. Pregnancy and tuberculosis treatment or prophylaxis can affect efavirenz pharmacokinetics, maternal human immunodeficiency virus type 1 (HIV-1) treatment outcomes, and mother-to-child transmission (MTCT) risk. Methods. We evaluated a prospective cohort of pregnant, HIV-infected women with and without tuberculosis in Soweto, South Africa. Pharmacokinetic sampling was performed at gestation week 37 and during the postpartum period. Efavirenz trough concentrations (C-min) were predicted using population pharmacokinetic models. HIV-viral load was measured at delivery for mothers and at 6 weeks of age for infants. Results. Ninety-seven women participated; 44 had tuberculosis. Median efavirenz C-min during pregnancy was 1.35 mu g/mL (interquartile range [IQR], 0.90-2.07 mu g/mL; 27% had an efavirenz C-min of <1 mu g/mL),compared with a median postpartum value of 2.00 mu g/mL (IQR, 1.40-3.59 mu g/mL; 13% had an efavirenz C-min of <1 mu g/mL). A total of 72% of pregnant women with extensive CYP2B6 genotypes had an efavirenz C-min of < 1 mu g/mL. Rifampin did not reduce the efavirenz C-min. Isoniazid (for prophylaxis or treatment), though, reduced the rate of efavirenz clearance. At delivery, median durations of ART were 13 weeks (IQR, 9-18 weeks) and 21 weeks (IQR, 13-64 weeks) for women with and those without tuberculosis, respectively; 55% and 83%, respectively, had a viral load of < 20 copies/mL (P = .021). There was 1 case of MTCT. Conclusions. Pregnancy increased the risk of low efavirenz concentrations, but MTCT was rare. A detectable HIV-viral load at delivery was more common among pregnant women with tuberculosis, in whom ART was generally initiated later.
    The Journal of Infectious Diseases 07/2014; 211(2). DOI:10.1093/infdis/jiu429 · 5.78 Impact Factor
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    ABSTRACT: Introduction Globally, hepatitis B virus (HBV) infection is the leading cause of liver-related mortality. Newborn vaccination, maternal antiviral therapy and administering hepatitis B immune globulin shortly after birth can greatly reduce the risk of perinatal and infant infection. However, evidence-based policy regarding these interventions in Africa is hampered by gaps in knowledge of HBV epidemiology. We describe maternal chronic hepatitis B (CHB) prevalence and infant infection during the first year of life within a cohort of women living with HIV. Methods We recruited and prospectively followed pregnant women living with HIV and their infants from prenatal clinics in an urban area of South Africa. Hepatitis B surface antigen, anti-hepatitis B surface antibodies and HBV DNA were assessed in all women. Hepatitis B testing was also performed at 6 and 52 weeks for all infants born to mothers with either positive surface antigen or detectable HBV DNA. Results We enrolled 189 women with a median age of 29 years and median CD4 count of 348 cells/mm3. Fourteen had a positive surface antigen (7.4%), of which six were positive for “e” antigen. An additional three had detectable HBV DNA without positive surface antigen. One infant developed CHB and three others had evidence of transmission based on positive HBV DNA assays. HBV vaccinations were delivered at six weeks of life to all infants. Conclusions Our findings highlight the risk of peripartum HBV transmission in this setting. Approaches to reducing this transmission should be considered.
    Journal of the International AIDS Society 05/2014; 17(1):18871. DOI:10.7448/IAS.17.1.18871 · 4.21 Impact Factor
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    ABSTRACT: CD4 count is a proxy for the extent of immune deficiency and declines in CD4 count are a measure of disease progression. Decline in CD4 count is an important component: for estimating benefits of ARV treatment; for individual level counselling on the rapidity of untreated disease progression and prognosis; and can be used in planning demand for health services. Our objective is to report CD4 decline and changes in viral load (VL) in a group of HIV-infected adults enrolled in a randomized trial of preventive treatment for TB in South Africa where clade C infection predominates. HIV-infected, tuberculin skin test positive adults who were not eligible for antiretroviral (ARV) treatment were randomized to a trial of preventive treatment from 2003-2005. VL and CD4 count were assessed at enrollment and CD4 counts repeated at least annually. During follow-up, individuals whose CD4 counts decreased to <200 cells/mm3 were referred for antiretroviral therapy (ART) and were analytically censored. 1106 ARV naïve adults were enrolled. Their median age was 30 years and male to female ratio was 1∶5. Median baseline CD4 count was 490 cells/mm3 (IQR 351-675). The overall mean decline in CD4 count was 61 cells/mm3 per annum. Adjusting for age, gender, baseline hemoglobin, smoking and alcohol use had little impact on the estimate of CD4 decline. However, VL at baseline had a major impact on CD4 decline. The percent decline in CD4 count was 13.3% (95% CI 12.0%, 14.7%), 10.6% (95% CI 8.8%, 12.4%), and 13.8% (95% CI 12.1%, 15.5%) per annum for baseline VLs of <10,000 (N = 314), 10,001-100,000 (N = 338), >100,000 (N = 122) copies/ml. Our data suggests that six and a half years will elapse for an individual's CD4 count to decline from 750 to 350 cells/mm3 in the absence of ART.
    PLoS ONE 05/2014; 9(5):e96369. DOI:10.1371/journal.pone.0096369 · 3.53 Impact Factor
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    ABSTRACT: The prevalence of illicitly traded cigarettes in South Africa has been reported to be 40-50%. However, these estimates do not account for the more nuanced characteristics of the illicit cigarette trade. With the goal of better understanding contraband cigarettes in South Africa, this study piloted three methods for assessing the price, brands, pack features and smoker's views about illicit cigarettes in five cities/towns. Data were collected in June and July 2012. A convenience sample of three South African cities (Johannesburg, Durban and Nelspruit) and two smaller towns (Musina and Ficksburg) were chosen for this study. Three cross-sectional approaches were used to assess the characteristics of contraband cigarettes: (1) a dummy purchase of cigarettes from informal retailers, (2) the collection of discarded cigarette packs and (3) a survey of tobacco smokers. For the purposes of the survey, 40 self-reported smokers were recruited at taxi ranks in each downtown site. Adults who were over the age of 18 were asked to verbally consent to participate in the study and answer a questionnaire administered by a researcher. The leading reason for labelling a pack as illicit in each city/town was the absence of an excise stamp (28.6% overall), and the least common reason was an illegal tar or nicotine level (11.1% overall). The overall proportion of informal vendors who sold illicit cigarettes was 41%. Singles and packs of 20 were consistently cheaper at informal vendors. Survey participants' responses reflected varied perspectives on illicit cigarettes and purchasing preferences. Each approach generated an interesting insight into physical aspects of illicit cigarettes. While this pilot study cannot be used to generate generalisable statistics on illicit cigarettes, more systematic surveys of this nature could inform researchers' and practitioners' initiatives to combat illicit and legal cigarette sales and usage.
    BMJ Open 05/2014; 4(5):e004562. DOI:10.1136/bmjopen-2013-004562 · 2.06 Impact Factor
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    ABSTRACT: To report the incidence rates of TB and HIV in household contacts of index patients diagnosed with TB. A prospective cohort study in the Matlosana sub-district of North West Province, South Africa. Contacts of index TB patients received TB and HIV testing after counseling at their first household visit and were then followed up a year later, in 2010. TB or HIV diagnoses that occurred during the period were determined. For 2,377 household contacts, the overall observed TB incidence rate was 1.3 per 100 person years (95% CI 0.9-1.9/100py) and TB incidence for individuals who were HIV-infected and HIV seronegative at baseline was 5.4/100py (95% CI 2.9-9.0/100py) and 0.7/100py (95% CI 0.3-1.4/100py), respectively. The overall HIV incidence rate was 2.2/100py (95% CI 1.3-8.4/100py). In the year following a household case finding visit when household contacts were tested for TB and HIV, the incidence rate of both active TB and HIV infection was found to be extremely high. Clearly, implementing proven strategies to prevent HIV acquisition and preventing TB transmission and progression to disease remains a priority in settings such as South Africa.
    PLoS ONE 04/2014; 9(4):e95372. DOI:10.1371/journal.pone.0095372 · 3.53 Impact Factor
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    ABSTRACT: The tuberculin skin test (TST) is used to help diagnose tuberculosis (TB) in acutely ill hospitalised children. OBJECTIVE To investigate the potential augmentative effect of topical calcipotriol (a vitamin D analogue) or zinc on TST induration. Three TSTs were performed among 64 hospitalised children; each site was covered with topical aqueous cream (control), calcipotriol or zinc and assessed 24 and 48 h later by investigators blinded to all topical applications. TSTs were reactive in 15 (23.4%) children, of whom 13 (20.3%) were TST-positive. Topical calcipotriol and zinc induced TST positivity in two children with reactive but negative control TSTs. These treatments, however, did not significantly increase TST positivity rates. In children with reactive TSTs, the median 48 h induration diameter was not significantly different between the control, calcipotriol- or zinc-treated groups, which were respectively 12.0 (25%-75% IQR 5.0 - 18.0), 14.0 (25%-75% IQR 10.0 - 15.0) and 12.0 (25%-75% IQR 8.0 - 15.0) mm. Topical treatments did not induce TST reactivity or TST positivity in children with culture-confirmed TB disease (n = 4), human immunodeficiency virus infection (n= 18) or kwashiorkor (n = 9). Topical calcipotriol or zinc does not induce TST reactivity or significantly increase TST positivity rates in acutely ill hospitalised children. However, further studies are required to assess the effects of topical treatments on TST positivity in severely malnourished children.
    The International Journal of Tuberculosis and Lung Disease 04/2014; 18(4):388-93. DOI:10.5588/ijtld.13.0707 · 2.76 Impact Factor
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    International Journal of Infectious Diseases 04/2014; 21:325. DOI:10.1016/j.ijid.2014.03.1091 · 2.33 Impact Factor
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    ABSTRACT: To report the viral load and CD4 count in HIV-infected, antiretroviral naïve, first -time HIV-testers, not immediately eligible for treatment initiation by current South Africa treatment guidelines. This was a cross-sectional study in a high-volume, free-of-charge HIV testing centre in Soweto, South Africa. We enrolled first time HIV testers and collected demographic and risk-behaviour data and measured CD4 count and viral load. Between March and October 2011, a total of 4793 adults attended VCT and 1062 (22%) tested positive. Of the 1062, 799 (75%) were ART naïve and 348/799 (44%) were first-time HIV testers. Of this group of 348, 225 (65%) were female. Overall their median age, CD4 count and viral load was 34 years (IQR: 28-41), 364 (IQR: 238-542) cells/mm3 and 13,000 (IQR: 2050-98171) copies/ml, respectively. Female first time HIV testers had higher CD4 counts (419 IQR: 262-582 vs. 303 IQR: 199-418 cells/mm3) and lower viral loads (9,100 vs. 34,000 copies/ml) compared to males. Of 183 participants with CD4 count >350 cells/mm3, 62 (34%) had viral loads > 10,000 copies/ml. A large proportion of HIV infected adults not qualifying for immediate ART at the CD4 count threshold of 350 cells/mm3 have high viral loads. HIV-infected men at their first HIV diagnosis are more likely to have lower CD4 counts and higher viral loads than women.
    PLoS ONE 03/2014; 9(3):e90754. DOI:10.1371/journal.pone.0090754 · 3.53 Impact Factor
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    ABSTRACT: Research in the predictors of all-cause mortality in HIV-infected people has widely been reported in literature. Making an informed decision requires understanding the methods used. We present a review on study designs, statistical methods and their appropriateness in original articles reporting on predictors of all-cause mortality in HIV-infected people between January 2002 and December 2011. Statistical methods were compared between 2002-2006 and 2007-2011. Time-to-event analysis techniques were considered appropriate. Pubmed/Medline. Original English-language articles were abstracted. Letters to the editor, editorials, reviews, systematic reviews, meta-analysis, case reports and any other ineligible articles were excluded. A total of 189 studies were identified (n = 91 in 2002-2006 and n = 98 in 2007-2011) out of which 130 (69%) were prospective and 56 (30%) were retrospective. One hundred and eighty-two (96%) studies described their sample using descriptive statistics while 32 (17%) made comparisons using t-tests. Kaplan-Meier methods for time-to-event analysis were commonly used in the earlier period (n = 69, 76% vs. n = 53, 54%, p = 0.002). Predictors of mortality in the two periods were commonly determined using Cox regression analysis (n = 67, 75% vs. n = 63, 64%, p = 0.12). Only 7 (4%) used advanced survival analysis methods of Cox regression analysis with frailty in which 6 (3%) were used in the later period. Thirty-two (17%) used logistic regression while 8 (4%) used other methods. There were significantly more articles from the first period using appropriate methods compared to the second (n = 80, 88% vs. n = 69, 70%, p-value = 0.003). Descriptive statistics and survival analysis techniques remain the most common methods of analysis in publications on predictors of all-cause mortality in HIV-infected cohorts while prospective research designs are favoured. Sophisticated techniques of time-dependent Cox regression and Cox regression with frailty are scarce. This motivates for more training in the use of advanced time-to-event methods.
    PLoS ONE 02/2014; 9(2):e87356. DOI:10.1371/journal.pone.0087356 · 3.53 Impact Factor

Publication Stats

2k Citations
555.52 Total Impact Points

Institutions

  • 2006–2015
    • University of the Witwatersrand
      • Perinatal HIV Research Unit
      Johannesburg, Gauteng, South Africa
  • 2007–2014
    • Johns Hopkins University
      • Department of Medicine
      Baltimore, Maryland, United States
  • 2011
    • Johns Hopkins Bloomberg School of Public Health
      Baltimore, Maryland, United States
  • 2010–2011
    • Johns Hopkins Medicine
      Baltimore, Maryland, United States
    • University of Pretoria
      Πρετόρια/Πόλη του Ακρωτηρίου, Gauteng, South Africa
  • 2008
    • Alpert Medical School - Brown University
      Providence, Rhode Island, United States