Shahid Ullah

Dr. Shahid Ullah

College of Medicine and Public Health, Flinders University, Adelaide, SA 5001, Australia

Research Focus & Metrics

Academic Career Length

34Years (1993-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2007 in Computational Statistics & Data Analysis
Verified
Journal Article
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RHRob Hyndman
Rob Hyndman
SUShahid Ullah
Shahid Ullah

19 March 2013 in BMC Medical Research Methodology
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Journal Article
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SUShahid Ullah
Shahid Ullah
CFCaroline F Finch
Caroline F Finch
Functional data analysis (FDA) is increasingly being used to better analyze, model and predict time series data. Key aspects of FDA include the choice of smoothing technique, data reduction, adjustment for clustering, functional linear modeling and forecasting methods.

1 April 2012 in Journal of Strength & Conditioning Research
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Journal Article
Closed access
TGTim J Gabbett
Tim J Gabbett
SUShahid Ullah
Shahid Ullah
Ort athletes is nonexistent, with all published studies using subjective measures (e.g., ratings of perceived exertion) to quantify training loads. The purpose of this study was to investigate the risk of low-intensity (e.g., walking, jogging, total distances) and high-intensity (e.g., high acceleration and velocity efforts, repeated high-intensity exercise bouts) movement activities on lower body soft-tissue injury in elite team sport athletes. Thirty-four elite rugby league players participated in this study. Global positioning system data and the incidence of lower body soft-tissue injuries were monitored in 117 skill training sessions during the preseason and in-season periods. The frailty model (an extension of the Cox proportional regression model for recurrent events) was applied to calculate the relative risk of injury after controlling for all other training data. The risk of injury was 2.7 (95% confidence interval 1.2–6.5) times higher when very high–velocity running (i.e., sprinting) exceeded 9 m per session. Greater distances covered in mild, moderate, and maximum accelerations and low- and very low–intensity movement velocities were associated with a reduced risk of injury. These results demonstrate that greater amounts of very high–velocity running (i.e., sprinting) are associated with an increased risk of lower body soft-tissue injury, whereas distances covered at low and moderate speeds offer a protective effect against soft-tissue injury. From an injury prevention perspective, these findings provide empirical support for restricting the amount of sprinting performed in preparation for elite team sport competition. However, coaches should also consider the consequences of reducing training loads on the development of physical qualities and playing performance....

6 November 2014 in Cancer
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Journal Article
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TPTimothy J Price
Timothy J Price
CBCarol Beeke
Carol Beeke
SUShahid Ullah
Shahid Ullah
RPRobert Padbury
Robert Padbury
GMGuy Maddern
Guy Maddern
CKChristos Karapetis
Christos Karapetis
BACKGROUND: Previous reports have described differences in biology and outcome for colorectal cancer based on whether the primary is right or left sided. Further division by right, left, and rectum or even exact primary site has also been explored. Possible differences in response to biological agents have also been reported based on side of primary lesion.METHODS: We explored the South Australian registry for metastatic colorectal cancer to assess if there were any differences in patient characteristics, prognostic markers, and treatment received and outcomes based on whether the primary was right or left sided. We also explored if differences exist based on left colon and rectum and by exact primary site.RESULTS: Two thousand nine hundred seventy‐two patients were analyzed. Thirty‐five percent had a right‐sided primary. The median overall survival for the entire group right versus left was 9.6 versus 20.3 months (P < .001). Multivariate analysis confirmed side of primary as an independent prognostic factor. For the group that had active therapy, defined as chemotherapy (± metastasis resection), median overall survival was right, 18.2 months; and left, 29.4 months (P < .001). Importantly, we found no suggestion of major differences if left side was divided by left colon and rectum, and trends by individual site still supported a left and right division.CONCLUSIONS: Patients with a right‐sided primary have more negative prognostic factors and indeed have inferior outcomes compared with those with a left‐sided primary. Our data with further breakdown by exact site still favor a simple left‐versus‐right division moving forward for metastatic colorectal cancer. Cancer 2015;121:830–835. © 2014 American Cancer Society.

1 January 2015 in HPB
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MBMark Brooke-Smith
Mark Brooke-Smith
JFJoan Figueras
Joan Figueras
SUShahid Ullah
Shahid Ullah
MRMyrddin Rees
Myrddin Rees
JVJean-Nicolas Vauthey
Jean-Nicolas Vauthey
RPRobert Padbury
Robert Padbury
The International Study Group for Liver Surgery (ISGLS) proposed a definition for bile leak after liver surgery. A multicentre international prospective study was designed to evaluate this definition. Data collected prospectively from 949 consecutive patients on specific datasheets from 11 international centres were collated centrally. Bile leak occurred in 69 (7.3%) of patients, with 31 (3.3%), 32 (3.4%) and 6 (0.6%) classified as grade A, B and C, respectively. The grading system of severity correlated with the Dindo complication classification system (P < 0.001). Hospital length of stay was increased when bile leak occurred, from a median of 7 to 15 days (P < 0.001), as was intensive care stay (P < 0.001), and both correlated with increased severity grading of bile leak (P < 0.001). 96% of bile leaks occurred in patients with intra-operative drains. Drain placement did not prevent subsequent intervention in the bile leak group with a 5-15 times greater risk of intervention required in this group (P < 0.001). The ISGLS definition of bile leak after liver surgery appears robust and intra-operative drain usage did not prevent the need for subsequent drain placement.

14 February 2019 in Journal of the American Society of Nephrology
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EAEric H. Au
Eric H. Au
JCJeremy R. Chapman
Jeremy R. Chapman
JCJonathan C. Craig
Jonathan C. Craig
WLWai H. Lim
Wai H. Lim
ATArmando Teixeira-Pinto
Armando Teixeira-Pinto
GWGermaine Wong
Germaine Wong
Significance Statement: Patients with ESRD experience a substantially increased incidence of cancer, but few studies have examined patterns of cancer mortality among such patients. This population-based cohort study of Australian patients who initiated dialysis or received a kidney transplant from 1980 to 2014 found that the risk of cancer-related death among 52,936 patients on dialysis and 16,820 kidney transplant recipients was 2.5 times higher than that of age- and sex-matched controls in the general population. For patients on dialysis, increased cancer mortality is primarily from cancers that caused ESRD; among transplant recipients, the increase is largely due to de novo cancers. Additional efforts are required to clarify factors and mechanisms involved in increased cancer risk and to improve early detection and management of cancer in this population. Background: Patients with ESRD have a substantially increased cancer risk, but few studies have examined the patterns of cancer mortality along a patient's journey from dialysis to transplantation. Methods: We identified all Australian patients on dialysis and patients with transplants from 1980 to 2014 from the Australia and New Zealand Dialysis and Transplant Registry. Using standardized mortality ratios (SMRs), we compared cancer mortality among patients on dialysis and patients with transplants versus the general population (overall and by age, sex, year, and site); we also performed a subgroup analysis excluding patients with preexisting cancers. Results: We followed 52,936 patients on dialysis and 16,820 transplant recipients for 170,055 and 128,352 patient-years, respectively. There were 2739 cancer deaths among patients on dialysis and 923 cancer deaths among transplant recipients. Overall, cancer SMRs were 2.6 for patients on dialysis and 2.7 for transplant recipients. For patients on dialysis, SMRs were highest for multiple myeloma (30.5), testicular cancer (17.0), and kidney cancer (12.5); for transplant recipients, SMRs were highest for non-Hodgkin lymphoma (10.7), kidney cancer (7.8), and melanoma (5.8). Some 61.0% of patients on dialysis and 9.6% of transplant recipients who experienced cancer death had preexisting cancer. The SMRs for de novo cancer was 1.2 for patients on dialysis and 2.6 for transplant recipients. Conclusions: Patients on dialysis and transplant recipients experienced >2.5-fold increased risk of cancer death compared with the general population. This increased risk was largely driven by preexisting cancers in patients on dialysis and de novo cancers in patients with transplants.