Design Details

1. What is the source of data (eg, cohort, RCT, registry data)?

Domain - Source of data. Please, provide the study design


	Retrospective cohort Prospective cohort randomized controlled trial (post-hoc analysis) registry data other (please, specify)

2. What was the recruitment method?

Domain - Participants. Please, provide how study population was gathered.


	all consecutive patients random sample non-random sampling other (please, specify)

3. The country of recruitment

Domain - Participants. Please, provide the country (countries) of the study.


	Japan

4. number of centres number of centres

Domain - Participants


	tertiary non-tertiary university hospital general hospital military hospital other


	only STEMI only NSTEMI only MI NST-ACS only stable CAD different clinical forms of CAD after PCI ACS other

7. Exclusion criteria

Domain - Participants


	missing PLT

8. Details of treatments received (if relevant)

Domain - Participant. Please, specify additional details. Choose all relevant options


	DES BMS ticagrelor clopidogrel prasugrel GP2b/3a inhibitors scaffolds other

9. Study dates

Domain - Participants


	2005-2007, 2010, 2011, respectively

Arms

Arm Name	Arm Description
Baseline platelet values	The study provided data on prognostic value of baseline platelet count.

Arm Details

1. Definition and method for measurement of prognostic factors

Domain - Prognostic factors. Please, provide definitions of thrombocytopenia or thrombocytosis if relevant 

Baseline platelet values


Definitions	severe thrombocytopenia (PLT value) moderate thrombocytopenia (PLT value) mild thrombocytopenia (PLT value) any thrombocytopenia (PLT value) normal values of PLT thrombocytosis (PLT value) PLT as a continuous variable (specify the unit increase) other
Blood analyzer used	not reported

2. Timing of PLT measurement (eg, at patient presentation, diagnosis, treatment initiation, at the end of PCI)

Domain - Prognostic factor. 

Baseline platelet values


	baseline PLT (specify the time of measurement)

3. Were prognostic factors assessed blinded for outcome, and for each other (if relevant)?

Domain - Prognostic Factor.

Baseline platelet values


	Yes No Unknown Other

4. Handling of prognostic factors in the analysis (eg, continuous, linear, non-linear transformations or categorised)

Domain - Prognostic factor

Baseline platelet values


	continuous categorised (specify cutpoints) linear (specify unit) non-linear transformations (splines, polynomials, or other)

Sample Characteristics

1. Was a sample size calculation conducted?

Domain - Sample size. Sample size calculation might be provided in the protocol published previously.

Baseline platelet values


	Yes (specify how) No Unknown

2. What is the number of included participants?

Domain - Sample size

Baseline platelet values

3. What is the number of patients experienced outcomes?

Domain - Sample size. If several endpoints are reported, please, provide the number of primary endpoints

Baseline platelet values


MACE

4. Number of outcomes or events in relation to the number of candidate prognostic factors (events per variable)

Domain - Sample size. For the primary endpoint

Baseline platelet values

5. Number of participants with any missing value (in the prognostic factors and outcomes)

Domain - Missing data. Please, provide data on the number of participants with any missing value in the the prognostic factors?

Baseline platelet values


	Yes, reported (specify the number) not reported no missing value other

6. Details of attrition (loss to follow-up) and, for time-to-event outcomes, number of censored observations (ideally in each category for those categorical prognostic factors of interest)

Domain - Missing data.

Baseline platelet values


	Provided, in general (specify the number) Provided, for each category of baseline PLT (specify the number) Not provided Other

7. Handling of missing data (eg, complete case analysis, imputation, or other methods)

Domain - Missing Data

Baseline platelet values


	Not reported complete case analysis imputation other

8. Modelling method (eg, linear, logistic, Cox, parametric survival, competing risks) regression)

Domain - Analysis. 


	Logistic regression Cox regression parametric survival regression competing risks regression not provided other

9. How modelling assumptions were checked; in particular, for time-to-event outcomes and the analysis of hazard ratios, the method for assessing non-proportional hazards (non-constant hazard ratios over time)

Domain - Analysis.

Baseline platelet values


	checked (specify the method) not checked unknown

10. Method for selection of prognostic factors for inclusion in multivariable modelling

Domain - Analysis.

Baseline platelet values


	all candidate prognostic factors considered preselection of established prognostic factors, retain only those significant from univariable analysis unknown other

11. Method for selection or exclusion of prognostic factors during multivariable modelling, and criteria used for any selection or exclusion

Domain - Analysis

Baseline platelet values


Method for selection or exclusion	backward selection forward selection full model approach unknown other
criteria used for any selection	P value Akaike information criterion Unknown other

12. Method of handling each continuous prognostic factor

Domain - Analysis.

Baseline platelet values


Cutpoints	100, 150
Units for linear variable

13. Number and set of adjustment factors

Domain - Results

Baseline platelet values


Number
Set	from Table 1

14. Interpretation of presented results

Domain - Interpretation

Baseline platelet values


	provided not provided other

15. Comparison with other studies, discussion of generalisability, strengths and limitations

Domain - Interpretation

Baseline platelet values


	provided not provided other

Outcomes

Type	Domain	Specific measurement (i.e., tool/definition/specific outcome)	Populations	Timepoints
Categorical	Baseline platelet values	Major adverse cardiac and cerebrovascular events	All Participants	long-term follow-up
Categorical	Baseline platelet values	Major bleeding	All Participants	long-term follow-up
Categorical	Baseline platelet values	All-cause mortality	All Participants	long-term follow-up
Categorical	Baseline platelet values	CV mortality	All Participants	long-term follow-up
Categorical	Baseline platelet values	Myocardial infarction	All Participants	long-term follow-up
Categorical	Baseline platelet values	All stroke	All Participants	long-term follow-up
Categorical	Baseline platelet values	Ischemic stroke	All Participants	long-term follow-up
Categorical	Baseline platelet values	Hemorrhagic stroke	All Participants	long-term follow-up
Categorical	Baseline platelet values	unplanned revascularization	All Participants	long-term follow-up

Outcome Details

1. Definition and method for measurement of outcomes

Domain - Outcomes.  Please, specify the used definitions (international or self-defined) and method for measurement

Baseline platelet values


Definition	"composite of myocardial infarction (MI) and ischemic stroke (fatal or nonfatal)"
Method for measurement	National Registry of death Electronic Health Records Medical records telephone interviews Clinical visits Questionnaire Not reported Other

Baseline platelet values


Definition	GUSTO
Method for measurement	National Registry of death Electronic Health Records Medical records telephone interviews Clinical visits Questionnaire Not reported Other


Definition	death from any cause
Method for measurement	National Registry of death Electronic Health Records Medical records telephone interviews Clinical visits Questionnaire Not reported Other


Definition	"Death without obvious non-cardiac cause was classified as cardiac death."
Method for measurement	National Registry of death Electronic Health Records Medical records telephone interviews Clinical visits Questionnaire Not reported Other

Baseline platelet values


Definition	ARTS and ARC definitions
Method for measurement	National Registry of death Electronic Health Records Medical records telephone interviews Clinical visits Questionnaire Not reported Other


Definition	"Stroke was defined as ischemic or haemorrhagic stroke either occurring during the index hospitalization or requiring hospitalization with symptoms lasting >24 hour. "
Method for measurement	National Registry of death Electronic Health Records Medical records telephone interviews Clinical visits Questionnaire Not reported Other

Baseline platelet values


Definition	"Haemorrhagic infarction was classified into ischemic stroke based on its primary cause."
Method for measurement	National Registry of death Electronic Health Records Medical records telephone interviews Clinical visits Questionnaire Not reported Other

Baseline platelet values


Definition	"Haemorrhagic infarction was classified into ischemic stroke based on its primary cause."
Method for measurement	National Registry of death Electronic Health Records Medical records telephone interviews Clinical visits Questionnaire Not reported Other

Baseline platelet values


Definition	ARC
Method for measurement	National Registry of death Electronic Health Records Medical records telephone interviews Clinical visits Questionnaire Not reported Other

2. Was the same outcome definition (and method for measurement) used in all participants?

Domain - Outcomes

Baseline platelet values


	Yes No Unknown Other

Baseline platelet values


	Yes No Unknown Other

Baseline platelet values


	Yes No Unknown Other

Baseline platelet values


	Yes No Unknown Other

Baseline platelet values


	Yes No Unknown Other

Baseline platelet values


	Yes No Unknown Other

Baseline platelet values


	Yes No Unknown Other

Baseline platelet values


	Yes No Unknown Other

Baseline platelet values


	Yes No Unknown Other

3. Types of outcomes (eg, single or combined endpoints)?

Domain - Outcomes.

Baseline platelet values


	Single combine other

Baseline platelet values


	Single combine other

Baseline platelet values


	Single combine other

Baseline platelet values


	Single combine other

Baseline platelet values


	Single combine other

Baseline platelet values


	Single combine other

Baseline platelet values


	Single combine other

Baseline platelet values


	Single combine other

Baseline platelet values


	Single combine other

4. Were the outcomes assessed without knowledge of the candidate prognostic factors (that is, blinded)?

Domain - Outcomes.

Baseline platelet values


	Yes, blinded No, unblinded Unknown Other

Baseline platelet values


	Yes, blinded No, unblinded Unknown Other

Baseline platelet values


	Yes, blinded No, unblinded Unknown Other

Baseline platelet values


	Yes, blinded No, unblinded Unknown Other

Baseline platelet values


	Yes, blinded No, unblinded Unknown Other

Baseline platelet values


	Yes, blinded No, unblinded Unknown Other

Baseline platelet values


	Yes, blinded No, unblinded Unknown Other

Baseline platelet values


	Yes, blinded No, unblinded Unknown Other

Baseline platelet values


	Yes, blinded No, unblinded Unknown Other

5. Were candidate prognostic factors part of the outcome (eg, when using a panel or consensus outcome measurement)?

Domain - Outcomes.

Baseline platelet values


	Yes No Other

Baseline platelet values


	Yes No Other

Baseline platelet values


	Yes No Other

Baseline platelet values


	Yes No Other

Baseline platelet values


	Yes No Other

Baseline platelet values


	Yes No Other

Baseline platelet values


	Yes No Other

Baseline platelet values


	Yes No Other

Baseline platelet values


	Yes No Other

6. Time of outcome occurrence or summary of duration of follow-up

Domain - Outcomes

Baseline platelet values


	3 years

Baseline platelet values


	3 years

Baseline platelet values


	3 years

Baseline platelet values


	3 years

Baseline platelet values


	3 years

Baseline platelet values


	3 years

Baseline platelet values


	3 years

Baseline platelet values


	3 years

Baseline platelet values


	3 years

Risk of Bias Assessment

1. 1. Study Participation

Hayden JA, van der Windt DA, Cartwright JL, Côté P, Bombardier C. Assessing bias in studies of prognostic factors. Ann Intern Med. 2013 Feb 19;158(4):280-6. 


The source population or population of interest is adequately described for key characteristics (LIST).	Yes Partial No unsure
The sampling frame and recruitment are adequately described, including methods to identify the sample sufficient to limit potential bias (number and type used, e.g., referral patterns in health care)	Yes Partial No Unsure
Period of recruitment is adequately described	Yes Partial No Unsure
Place of recruitment (setting and geographic location) are adequately described	Yes Partial No Unsure
Inclusion and exclusion criteria are adequately described (e.g., including explicit diagnostic criteria or “zero time” description).	Yes Partial No Unsure
There is adequate participation in the study by eligible individuals	Yes Partial No Unsure
The baseline study sample (i.e., individuals entering the study) is adequately described for key characteristics	Yes Partial No Unsure
Summary Study participation

2. 2. Study Attrition

Hayden JA, van der Windt DA, Cartwright JL, Côté P, Bombardier C. Assessing bias in studies of prognostic factors. Ann Intern Med. 2013 Feb 19;158(4):280-6.


Response rate (i.e., proportion of study sample completing the study and providing outcome data) is adequate.	Yes Partial No Unsure
Attempts to collect information on participants who dropped out of the study are described.	Yes Partial No Unsure
Reasons for loss to follow-up are provided.	Yes Partial No Unsure
Participants lost to follow-up are adequately described for key characteristics.	Yes Partial No Unsure
There are no important differences between key characteristics (LIST) and outcomes in participants who completed the study and those who did not.	Yes Partial No Unsure
Study Attrition Summary

3. 3. Prognostic Factor Measurement

 Hayden JA, van der Windt DA, Cartwright JL, Côté P, Bombardier C. Assessing bias in studies of prognostic factors. Ann Intern Med. 2013 Feb 19;158(4):280-6. 

	A clear definition or description of 'PF' is provided
A clear definition or description of 'PF' is provided
Method of PF measurement is adequately valid and reliable to limit misclassification bias
Appropriate cut-points are used.
measurement of PF is the same for all study participants
Adequate proportion of the study sample has complete data
Appropriate methods of imputation
Summary

4. 4. Outcome Measurement

Hayden JA, van der Windt DA, Cartwright JL, Côté P, Bombardier C. Assessing bias in studies of prognostic factors. Ann Intern Med. 2013 Feb 19;158(4):280-6. 


A clear definition of outcome is provided
The method of outcome measurement used is adequately valid and reliable to limit misclassification bias
outcome measurement is the same for all study participants.
Summary

5. 5. Study Confounding

Hayden JA, van der Windt DA, Cartwright JL, Côté P, Bombardier C. Assessing bias in studies of prognostic factors. Ann Intern Med. 2013 Feb 19;158(4):280-6. 


All important confounders are measured.
Clear definitions of the important confounders measured are provided
Valid and Reliable Measurement of Confounders
confounding measurement are the same for all study participants.
Appropriate methods are used for imputation
Important potential confounders are accounted for in the study design
Important potential confounders are accounted for in the analysis
Summary

6. 6. Statistical Analysis and Reporting

Hayden JA, van der Windt DA, Cartwright JL, Côté P, Bombardier C. Assessing bias in studies of prognostic factors. Ann Intern Med. 2013 Feb 19;158(4):280-6. 


There is sufficient presentation of data to assess the adequacy of the analysis.
The strategy for model building is appropriate
The selected statistical model is adequate
There is no selective reporting of results.
Summary

Results

Categorical

Baseline platelet values (Major adverse cardiac and cerebrovascular events)

All Participants
		Descriptive Statistics		Between Arm Comparisons
		Baseline platelet values
long-term follow-up
	HR		Odds Ratio (OR)
	Total (N analyzed)		95% CI low (OR)
	Events		95% CI high (OR)
	Percentage		p value
		Within Arm Comparisons		Net Comparisons
		Baseline platelet values

Baseline platelet values (Major bleeding)

All Participants
		Descriptive Statistics		Between Arm Comparisons
		Baseline platelet values
long-term follow-up
	HR		Odds Ratio (OR)
	Total (N analyzed)		95% CI low (OR)
	Events		95% CI high (OR)
	Percentage		p value
		Within Arm Comparisons		Net Comparisons
		Baseline platelet values

Baseline platelet values (All-cause mortality)

All Participants
		Descriptive Statistics		Between Arm Comparisons
		Baseline platelet values
long-term follow-up
	HR		Odds Ratio (OR)
	Total (N analyzed)		95% CI low (OR)
	Events		95% CI high (OR)
	Percentage		p value
		Within Arm Comparisons		Net Comparisons
		Baseline platelet values

Baseline platelet values (CV mortality)

All Participants
		Descriptive Statistics		Between Arm Comparisons
		Baseline platelet values
long-term follow-up
	HR		Odds Ratio (OR)
	Total (N analyzed)		95% CI low (OR)
	Events		95% CI high (OR)
	Percentage		p value
		Within Arm Comparisons		Net Comparisons
		Baseline platelet values

Baseline platelet values (Myocardial infarction)

All Participants
		Descriptive Statistics		Between Arm Comparisons
		Baseline platelet values
long-term follow-up
	HR		Odds Ratio (OR)
	Total (N analyzed)		95% CI low (OR)
	Events		95% CI high (OR)
	Percentage		p value
		Within Arm Comparisons		Net Comparisons
		Baseline platelet values

Baseline platelet values (All stroke)

All Participants
		Descriptive Statistics		Between Arm Comparisons
		Baseline platelet values
long-term follow-up
	HR		Odds Ratio (OR)
	Total (N analyzed)		95% CI low (OR)
	Events		95% CI high (OR)
	Percentage		p value
		Within Arm Comparisons		Net Comparisons
		Baseline platelet values

Baseline platelet values (Ischemic stroke)

All Participants
		Descriptive Statistics		Between Arm Comparisons
		Baseline platelet values
long-term follow-up
	HR		Odds Ratio (OR)
	Total (N analyzed)		95% CI low (OR)
	Events		95% CI high (OR)
	Percentage		p value
		Within Arm Comparisons		Net Comparisons
		Baseline platelet values

Baseline platelet values (Hemorrhagic stroke)

All Participants
		Descriptive Statistics		Between Arm Comparisons
		Baseline platelet values
long-term follow-up
	HR		Odds Ratio (OR)
	Total (N analyzed)		95% CI low (OR)
	Events		95% CI high (OR)
	Percentage		p value
		Within Arm Comparisons		Net Comparisons
		Baseline platelet values

Baseline platelet values (unplanned revascularization)

All Participants
		Descriptive Statistics		Between Arm Comparisons
		Baseline platelet values
long-term follow-up
	HR		Odds Ratio (OR)
	Total (N analyzed)		95% CI low (OR)
	Events		95% CI high (OR)
	Percentage		p value
		Within Arm Comparisons		Net Comparisons
		Baseline platelet values

Extraction form for project: The prognostic value of a baseline platelet count in patients treated with percutaneous coronary intervention: a systematic review and dose-response meta-analysis

Design Details

1. What is the source of data (eg, cohort, RCT, registry data)?

2. What was the recruitment method?

3. The country of recruitment

4. number of centres number of centres

5. Settings for study participants

6. Inclusion criteria

7. Exclusion criteria

8. Details of treatments received (if relevant)

9. Study dates

Arms

Arm Details

1. Definition and method for measurement of prognostic factors

Baseline platelet values

2. Timing of PLT measurement (eg, at patient presentation, diagnosis, treatment initiation, at the end of PCI)

Baseline platelet values

3. Were prognostic factors assessed blinded for outcome, and for each other (if relevant)?

Baseline platelet values

4. Handling of prognostic factors in the analysis (eg, continuous, linear, non-linear transformations or categorised)

Baseline platelet values

Sample Characteristics

1. Was a sample size calculation conducted?

Baseline platelet values

2. What is the number of included participants?

Baseline platelet values

3. What is the number of patients experienced outcomes?

Baseline platelet values

4. Number of outcomes or events in relation to the number of candidate prognostic factors (events per variable)

Baseline platelet values

5. Number of participants with any missing value (in the prognostic factors and outcomes)

Baseline platelet values

6. Details of attrition (loss to follow-up) and, for time-to-event outcomes, number of censored observations (ideally in each category for those categorical prognostic factors of interest)

Baseline platelet values

7. Handling of missing data (eg, complete case analysis, imputation, or other methods)

Baseline platelet values

8. Modelling method (eg, linear, logistic, Cox, parametric survival, competing risks) regression)

Baseline platelet values

9. How modelling assumptions were checked; in particular, for time-to-event outcomes and the analysis of hazard ratios, the method for assessing non-proportional hazards (non-constant hazard ratios over time)

Baseline platelet values

10. Method for selection of prognostic factors for inclusion in multivariable modelling

Baseline platelet values

11. Method for selection or exclusion of prognostic factors during multivariable modelling, and criteria used for any selection or exclusion

Baseline platelet values

12. Method of handling each continuous prognostic factor

Baseline platelet values

13. Number and set of adjustment factors

Baseline platelet values

14. Interpretation of presented results

Baseline platelet values

15. Comparison with other studies, discussion of generalisability, strengths and limitations

Baseline platelet values

Outcomes

Outcome Details

1. Definition and method for measurement of outcomes

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

2. Was the same outcome definition (and method for measurement) used in all participants?

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

3. Types of outcomes (eg, single or combined endpoints)?

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values

Baseline platelet values