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Sean Ong

@seanong.bsky.social

ID doc and joint PhD candidate at University of Toronto + University of Melbourne. Talk to me about clinical trial design and methodology, bloodstream infections, S. aureus, and Gram negatives ๐Ÿฆ  ๐Ÿ‡ธ๐Ÿ‡ฌ๐Ÿ‡จ๐Ÿ‡ฆ๐Ÿ‡ฆ๐Ÿ‡บ

1,003 Followers  |  166 Following  |  82 Posts  |  Joined: 12.11.2024  |  2.4591

Latest posts by seanong.bsky.social on Bluesky

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Quality-of-Care Indicator Adherence and Mortality Outcomes in MRSA Bacteremia This post hoc analysis of a randomized clinical trial investigates whether patient participation in clinical trials is associated with practitioner adherence to methicillin-resistant Staphylococcus au...

New post-hoc Camera-2 ๐Ÿ“ท post-hoc analysis out today regarding adherence to quality metrics in MRSA bacteremia.

Compared to similar non-trial population w/ MRSA bacteremia:
-No difference in ๐Ÿชฆ, BUT
-non-trial had less following of quality metrics (see โฌ‡๏ธ)

#IDSky

jamanetwork.com/journals/jam...

27.07.2025 00:59 โ€” ๐Ÿ‘ 5    ๐Ÿ” 3    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

This study was partly inspired after seeing a slide on @steventong.bsky.social's presentation about SAB trials at ESCMID 2024, after which we connected with the BACSARM and SAFO investigators to put this together. Conferences are a wonderful source of new project ideas and collaborations.

18.07.2025 00:57 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

Glad to have the opportunity to collaborate with Spanish colleagues on this. We conducted a pooled Bayesian post-hoc analysis of the BACSARM and SAFO trials evaluating combination therapy with fosfomycin for SAB. The door may not be closed on adjunctive fosfomycin! Justifies need for more RCTs.

18.07.2025 00:52 โ€” ๐Ÿ‘ 3    ๐Ÿ” 1    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
Evaluating the impact of a SIMPlified LaYered consent process on recruitment of potential participants to the Staphylococcus aureus Network Adaptive Platform trial: study protocol for a multicentre pr... Introduction Informed consent forms (ICFs) for randomised clinical trials (RCTs) can be onerous and lengthy. The process has the potential to overwhelm patients with information, leading them to miss ...

This is a fantastic example of a Study Within A Trial (SWAT), incorporating research on RCT methods within a larger clinical trial. We are currently conducting a similar SWAT, SIMPLY-SNAP, which looks at the impact of simplified layered consent on recruitment to SNAP: doi.org/10.1136/bmjo...

26.06.2025 03:03 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Trials Within Trialsโ€”Optimizing the Delivery of RCTs In the latest issue of JAMA, Johansen and colleagues1 report the results of a trial that investigated the impact of digital recruitment letter formats on recruitment to a larger clinical trial, the DA...

Thankful for another opportunity to write this editorial with @steventong.bsky.social in @jama.com: jamanetwork.com/journals/jam...

We discuss this trial, which evaluated the impact of different recruitment letter formats on RCT enrolment: jamanetwork.com/journals/jam...

26.06.2025 03:03 โ€” ๐Ÿ‘ 5    ๐Ÿ” 2    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

8/ We tried to write this review in an approachable way for clinicians who may not be entirely comfortable with statistics. Hopefully it is useful to some folks.

In a follow-up paper, we applied the different methods described in illustrative post-hoc analyses of BALANCE and CAMERA2. Stay tuned!

16.06.2025 01:52 โ€” ๐Ÿ‘ 2    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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7/ The nomenclature in the literature is inconsistent, and often mixes up outcomes, target parameters, and analytic methods. Confusingly, outcomes can be summarized using multiple different target parameters, which can be analyzed using multiple different methods. More than one way to skin a cat :)

16.06.2025 01:52 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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6/ Importantly, we should look at whether odds are proportional (known as the PO assumption), or minimally that the direction of effect is consistent across all levels of the ordinal scale. As long as the effect is consistent (as opposed to discordant), the common OR is clinically interpretable.

16.06.2025 01:52 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

5/ Parametric approaches can also be used for HCEs, commonly the proportional odds (PO) model. This estimates the common OR, interpreted as the odds a patient in one group has of being at least one step higher on the scale (i.e., having a better outcome) than a patient in the other group.

16.06.2025 01:52 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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4/ This results in three summary numbers: total number of wins, losses, and ties. These numbers can be used to calculate different treatment effect estimates: win ratio, win odds, net treatment benefit, NNT, and probabilistic index. (Don't let the math scare you, it's simpler than it looks!)

16.06.2025 01:52 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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3/ HCEs can also be analyzed using the generalized pairwise comparisons (GPC) method, where every patient in group 1 is compared to every patient in group 2 in all possible patient-pair combinations. A win is determined for each pair based on the hierarchical ordering of outcome components.

16.06.2025 01:52 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
Redirecting

2/ Studies using DOOR are often analyzed using the Mann-Whitney U test, comparing distribution of ranks across groups. This estimates the probability that a randomly selected patient in group 1 has a better outcome to one in group 2 (AKA probabilistic index).

doi.org/10.1016/j.cm...

16.06.2025 01:52 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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1/ HCEs combine features of composite and ordinal outcomes: they combine multiple clinical events (composite), but are also hierarchical as they establish a rank order of clinical importance across the different component events. A common example in ID is the DOOR outcome, a specific type of HCE.

16.06.2025 01:52 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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Making sense of hierarchical composite endpoints in randomized clinical trials โ€“ a primer for infectious disease clinicians and researchers Hierarchical composite endpoints (HCEs) are increasingly being used in infectious diseases research. In this review aimed at educating the clinical reader,

Our review on hierarchical composite endpoints (HCEs) has just been published in @cidjournal.bsky.social:
doi.org/10.1093/cid/...

We provide a conceptual overview of HCEs, explain the different associated target parameters and analytic methods.

@steventong.bsky.social @gurujosh.bsky.social

16.06.2025 01:52 โ€” ๐Ÿ‘ 10    ๐Ÿ” 4    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
Venn diagram with one circle representing ordinal endpoints (eg WHO clinical progression score for COVID, modified Rankin scale, Glasgow outcome score, etc), another representing composite endpoints (eg time to death, treatment failure, or disease recurrence), and area of overlap (hierarchical composite endpoints, eg DOOR and extensions as seen in REMAP-CAP).

Venn diagram with one circle representing ordinal endpoints (eg WHO clinical progression score for COVID, modified Rankin scale, Glasgow outcome score, etc), another representing composite endpoints (eg time to death, treatment failure, or disease recurrence), and area of overlap (hierarchical composite endpoints, eg DOOR and extensions as seen in REMAP-CAP).

Making sense of hierarchical composite endpoints in randomized clinical trials โ€“ a primer for infectious disease clinicians and researchers

@seanong.bsky.social @gurujosh.bsky.social @steventong.bsky.social and colleagues

Open Access #IDSky #MedSky

academic.oup.com/cid/advance-...

13.06.2025 19:30 โ€” ๐Ÿ‘ 32    ๐Ÿ” 12    ๐Ÿ’ฌ 3    ๐Ÿ“Œ 0
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Target Trial Emulation for Antibiotic Use in Acute COVID-19 This study by Pulia and colleagues1 reports results from a large population-based cohort using target trial emulation to examine the associations of antibiotic treatment with clinical outcomes in pati...

Honoured to be invited to write this commentary with @steventong.bsky.social, on an excellent target trial emulation study which showed that antibiotic use was not associated with improved outcomes in non-severe COVID-19.

jamanetwork.com/journals/jam...

#IDSky

20.05.2025 00:00 โ€” ๐Ÿ‘ 7    ๐Ÿ” 2    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 1
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๐Ÿ†• Evaluating BSI in Ontario we found #AMR was associated with a 10% โฌ†๏ธ risk of death equivalent to 1.2 deaths/100,000 people/year

These estimates are lower than those in previous literature, which may be due to robust adjustment for confounding

doi.org/10.1093/cid/...
@cidjournal.bsky.social

16.05.2025 00:31 โ€” ๐Ÿ‘ 4    ๐Ÿ” 1    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
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Evaluating Harms Associated With Prolonged Antibiotic Duration of Therapy in Community-Dwelling Older Adults: A Cohort Study Using Instrumental Variable Analysis Shorter courses of antibiotic therapy are increasingly recommended to reduce antibiotic exposure. However, quantifying the real-world impact of duration of therapy is hindered by bias common in observational studies.

Evaluating Harms Associated With Prolonged Antibiotic Duration of Therapy in Community-Dwelling Older Adults: A Cohort Study Using Instrumental Variable Analysis

#IDSky

10.05.2025 12:41 โ€” ๐Ÿ‘ 6    ๐Ÿ” 2    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0
Forest plot of 30 day all cause mortality which favors cefazolin (OR=0.73, 95%CI=0.62-0.85)

Forest plot of 30 day all cause mortality which favors cefazolin (OR=0.73, 95%CI=0.62-0.85)

Forest plot of discontinuation due to adverse effects which favors cefazolin (OR=0.13, 95%CI=0.06-0.27)

Forest plot of discontinuation due to adverse effects which favors cefazolin (OR=0.13, 95%CI=0.06-0.27)

Cefazolin vs Antistaphylococcal Penicillins for Treatment of Methicillin-Susceptible Staphylococcus aureus Bacteremia: A Systematic Review & Meta-Analysis

@connorprosty.bsky.social @seanong.bsky.social &c

Cefaz more effective, safer #idsky
www.clinicalmicrobiologyandinfection.com/article/S119... ๐Ÿ”“

09.05.2025 16:29 โ€” ๐Ÿ‘ 27    ๐Ÿ” 4    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 1

It's a reason some people might throw up to say the SNAP results don't apply to their setting... Because we only used (flu)cloxacillin in SNAP. So we did this SR/MA to try and address that.

10.05.2025 00:24 โ€” ๐Ÿ‘ 2    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

But at the same time I recognize that every trial/study setting has a unique sociodemographic context, so there isn't a one-size-fits-all solution! And being overly prescriptive and mandating reporting may also be counterproductive. As with most things, a nuanced approach is best.

07.05.2025 07:38 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

I'm not sure that is sufficient. We can't assume that trials are representative of the patient population in that hospital catchment area. There are many documented barriers from screening to trial enrolment. IMO it's better to transparently report granular data as much as is feasibly possible.

07.05.2025 07:30 โ€” ๐Ÿ‘ 0    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

Thank you! Indeed, lots to improve on how we collect and report these data.

07.05.2025 05:54 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

It's generally poor and inconsistent across most fields:
jamanetwork.com/journals/jam...
www.thelancet.com/journals/ecl...
bmjopen.bmj.com/content/12/8...

But to our knowledge, our study is the first to specifically examine the ID literature.

07.05.2025 02:46 โ€” ๐Ÿ‘ 3    ๐Ÿ” 0    ๐Ÿ’ฌ 0    ๐Ÿ“Œ 0

10/ Lastly โ€“ we collected a lot more data as part of this massive review of 1343 RCTs. I really have to thank the combined efforts of a multinational team of students and fellows in helping with data extraction. Keep a look out for more secondary papers from this dataset!

07.05.2025 00:55 โ€” ๐Ÿ‘ 3    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

9/ Our study shows that reporting of important sociodemographic variables was low, inconsistent, and has not improved over time. Consensus guidelines should outline the minimum set of variables that should be reported in RCTs, and describe the specific settings that require more detailed reporting.

07.05.2025 00:55 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

8/ Beyond the presence/absence of reporting, it is also important to ensure quality and consistency of reporting. E.g., 18% of studies that reported ethnicity in our review only reported binary categories (e.g., white vs non-white), which is inadequate in capturing the diversity of most populations.

07.05.2025 00:55 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

7/ In multivariable models, we found that subject area, funding source, health equity relatedness, use of a professional medical writer, and trial setting (high income vs LMIC) were independently associated with probability of reporting of ethnicity, education, or socioeconomic status.

07.05.2025 00:55 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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6/ Reporting of these variables also differed widely depending on subject area. E.g., RCTs studying viral infections, HIV/STIs, and COVID-19 had the highest reporting of ethnicity, while those studying tropical medicine, critical care, and antimicrobial stewardship/infection control had the lowest.

07.05.2025 00:55 โ€” ๐Ÿ‘ 1    ๐Ÿ” 0    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0
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5/ Almost all trials reported sex and/or gender. However, less than half (49.3%) reported ethnicity, and only a minority reported education level (9.0%), socioeconomic status (9.0%), and rurality (3.9%). Reporting of all these variables did not improve throughout the 10-year study period.

07.05.2025 00:55 โ€” ๐Ÿ‘ 3    ๐Ÿ” 1    ๐Ÿ’ฌ 1    ๐Ÿ“Œ 0

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