results

Presented At The Workshop On Clinical Research From HCor, São Paulo, Brasil, As Part Of The Clinical Research National Program Of The Brazilian Health Ministry (December 4, 2009)

Critical Appraisal of LiteratureEstimate of Clinical Benefits

The Roadmap for Evidence Based Clinical Practice

Suzana Alves da Silva, MD, MScCoordinator of Research & Development

Teaching and Research Center of Pró-Cardíaco

1domingo, 16 de maio de 2010

Center for Education Research and Evaluation

CLARITY Group

Teaching and Research Center of Pró-Cardíaco


Clinical Action DomainsTHERAPY DIAGNOSIS PROGNOSIS HARM

Ask

Acquire

Appraise

Ask

Acquire

Appraise

Ask

Acquire

Appraise

Ask

Acquire

Appraise

Apply Apply Apply Apply

The Action Domains


What are the most important results?


Critical Appraisal of the Results

TherapyDiagnosisDiagnosisDiagnosis PrognosisPrognosis

HarmTherapyPerformancePerformance Utility Performance Utility

Harm

Frequency

Effect

Impact

Precision

Pre-test prob Risk

RR, OR, HR LR RR, OR, HR

RR, OR, HR

RR, OR, HR

RR, OR, HR

RR, OR, HR

RD, NNT Pos-test prob RDRD RD RD, NNH

CI CI CICI CI CI CI


Absolute Risk at 1 yearControl Intervention


Absolute Risk at 1 year

0

0,2

0,4

0,6

0,8

Population A Population B Population C Population D

Control Intervention



0

0,2

0,4

0,6

0,8

80%Population A Population B Population C Population D




0

0,2

0,4

0,6

0,8

80% 40%Population A Population B Population C Population D




0

0,2

0,4

0,6

0,8

80% 40% 20%





0

0,2

0,4

0,6

0,8

80% 40% 20% 10%





0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0%





0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0%





0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0%





0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%




Risk DifferenceControle Intervenção

Impact Measure


Risk Difference

0

0,2

0,4

0,6

0,8

População A População B População C População D

Controle Intervenção

Impact Measure


Risk Difference

0

0,2

0,4

0,6

0,8

80% 60,0%População A População B População C População D


Impact Measure


Risk Difference

0

0,2

0,4

0,6

0,8

80% 60,0%População A População B População C População D


20%

Impact Measure


Risk Difference

0

0,2

0,4

0,6

0,8

80% 40%60,0% 30,0%População A População B População C População D


20%

Impact Measure


Risk Difference

0

0,2

0,4

0,6

0,8

80% 40%60,0% 30,0%População A População B População C População D


20%

10%

Impact Measure


Risk Difference

0

0,2

0,4

0,6

0,8

80% 40% 20%60,0% 30,0% 15,0%



20%

10%

Impact Measure


Risk Difference

0

0,2

0,4

0,6

0,8

80% 40% 20%60,0% 30,0% 15,0%



20%

10%

5%

Impact Measure


Risk Difference

0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20%

10%

5%

Impact Measure


Risk Difference

0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20%

10%

5% 2,5%

Impact Measure


0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20%

10%

5% 2,5%

Impact Measure


Other ways to express impact measures


Other ways to express impact measures

ARR NNT20% 100 20 5

X 1

10% 100 10 10

5% 100 5 20

2,5% 100 2,5 40


Measures of Effect or Association

✤Relative Risk✤Odds Ratio✤Harzard Ratio


What is Relative Risk then?

0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20%

10%

5% 2,5%



0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20%

10%

5% 2,5%

60 / 80 = 0,75



0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20%

10%

5% 2,5%

60 / 80 = 0,75

30 / 40 = 0,75



0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20%

10%

5% 2,5%

60 / 80 = 0,75

30 / 40 = 0,75

15 / 20= 0,75



0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20%

10%

5% 2,5%

60 / 80 = 0,75

30 / 40 = 0,75

15 / 20= 0,75 7,5 / 10

= 0,75


And Relative Risk Reduction?Control Intervention RR= 0,75


And Relative Risk Reduction?

0

0,2

0,4

0,6

0,8


Control Intervention RR= 0,75



0

0,2

0,4

0,6

0,8

80% 60,0%Population A Population B Population C Population D

Control Intervention RR= 0,75



0

0,2

0,4

0,6

0,8

80% 60,0%Population A Population B Population C Population D


20 / 80

RR= 0,75

RRR = 0,25



0

0,2

0,4

0,6

0,8

80% 40%60,0% 30,0%Population A Population B Population C Population D


20 / 80

RR= 0,75

RRR = 0,25



0

0,2

0,4

0,6

0,8

80% 40%60,0% 30,0%Population A Population B Population C Population D


20 / 80

10 / 40

RR= 0,75

RRR = 0,25

RRR = 0,25



0

0,2

0,4

0,6

0,8

80% 40% 20%60,0% 30,0% 15,0%



20 / 80

10 / 40

RR= 0,75

RRR = 0,25

RRR = 0,25



0

0,2

0,4

0,6

0,8

80% 40% 20%60,0% 30,0% 15,0%



20 / 80

10 / 40 5 / 20

RR= 0,75

RRR = 0,25

RRR = 0,25

RRR = 0,25



0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20 / 80

10 / 40 5 / 20

RR= 0,75

RRR = 0,25

RRR = 0,25

RRR = 0,25



0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20 / 80

10 / 40 5 / 20

2,5 / 10RR= 0,75

RRR = 0,25

RRR = 0,25

RRR = 0,25RRR = 0,25



0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20 / 80

10 / 40 5 / 20

2,5 / 10RR= 0,75

RRR = 0,25

RRR = 0,25

RRR = 0,25RRR = 0,25

RRR= 0,25



0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20 / 80

10 / 40 5 / 20

2,5 / 10RR= 0,75

RRR = 0,25

RRR = 0,25

RRR = 0,25RRR = 0,25

RRR= 0,25+



0

0,2

0,4

0,6

0,8

80% 40% 20% 10%60,0% 30,0% 15,0% 7,5%



20 / 80

10 / 40 5 / 20

2,5 / 10RR= 0,75

RRR = 0,25

RRR = 0,25

RRR = 0,25RRR = 0,25

RRR= 0,25+ = 1


Why the measures of association are more frequently used in Systematic Reviews?5 year mortality rate in the drug eluting stents trials: All Sirius - Sirius - Ravel

All - Sirius

Pache

Ravel

RR (95% CI) % Weight

48

19,9

32,1

1,32(0,63-2,78)

1,40(0,45-4,35)

1,72(0,75-3,95)

1,47 (0,89-241)

4,350,23

Overall 95% CI

Studies

1

Int J Epidemiol 2002;31:72-6.


Measures of EffectOdds Ratio

✤What is Odds?


Difference between Risk and Odds



Probability of Occurring

Probability of not Occurring Odds

P 1 - P P/(1-P)

Risk of occurring the number 1:

1/6

Risk of not occurring the

number 1:

5/61/5


Risk of occurring... Risk of not occurring... Odds

P 1 - P P/(1-P)

50% 50% 1

40% 60% 0,66

30% 70% 0,43

20% 80% 0,25

10% 90% 0,11

5% 95% 0,052



Difference between Risk and OddsRisk of occurring... Risk of not occurring... Odds

P 1 - P P/(1-P)

0,5 50% 1

0,4 60% 0,66

0,3 70% 0,43

0,2 80% 0,25

0,1 90% 0,11

0,05 95% 0,05217domingo, 16 de maio de 2010

Outcome +

Outcome - Risk Odds

Intervention 10 90 10% 10%/90%

Control 20 80 20% 20%/80%

RR = 0,5

OR = 0,4


Outcome +

Outcome - Risk Odds


Control 20 80 20% 20%/80%

RR = 0,5

OR = 0,4

RR = RA I/C


Outcome +

Outcome - Risk Odds


Control 20 80 20% 20%/80%

RR = 0,5

OR = 0,4

RR = RA I/C OR = Odds I/C


Measures of EffectHarzard Ratio

0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010

Intervention Control

Surv

ival

(%

)



0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010


RR = 5/30

Surv

ival

(%

)



0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010


0,17

Surv

ival

(%

)



0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010


RR = 10/50

0,17

Surv

ival

(%

)



0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010


0,17

0,2Surv

ival

(%

)



0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010


RR = 20/60

0,17

0,2Surv

ival

(%

)



0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010


0,17

0,20,33

Surv

ival

(%

)



0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010


RR = 30/65

0,17

0,20,33

Surv

ival

(%

)



0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010


0,17

0,20,33 0,46

Surv

ival

(%

)



0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010


RR = 70/70

0,17

0,20,33 0,46

Surv

ival

(%

)



0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010


0,17

0,20,33 0,46 1

Surv

ival

(%

)



0

25

50

75

100100

9590

80

70

30

100

70

50

4035

30

2005 2006 2007 2008 2009 2010


0,17

0,20,33 0,46 1

HR ≃ Average RR ≃ 0,43

Surv

ival

(%

)


Measures of PrecisionConfidence Intervals

95% dos

valores f(x)

! ! - 2" ! + 2" 0-1,96 +1,96

................

............

.........

......n re

sulta

dos

Medidas de Frequência

Medidas de Associação

Medidas de Impacto

Estimate Effect

Inferior Limit of 95% CI | | Superior Limit of 95% CI

Médias


Confidence Intervals5 year mortality in the drug-eluting stents trials: All Sirius - Sirius - Ravel

All - Sirius

Pache

Ravel


48

19,9

32,1

1,32(0,63-2,78)

1,40(0,45-4,35)

1,72(0,75-3,95)

1,47 (0,89-241)

4,350,23

Overall 95% CI

Studies

1

RR Int J Epidemiol 2002;31:72-6.



All - Sirius

Pache

Ravel


48

19,9

32,1

1,32(0,63-2,78)

1,40(0,45-4,35)

1,72(0,75-3,95)

1,47 (0,89-241)

4,350,23

Overall 95% CI

Studies

1

! ! - 2" ! + 2"




All - Sirius

Pache

Ravel


48

19,9

32,1

1,32(0,63-2,78)

1,40(0,45-4,35)

1,72(0,75-3,95)

1,47 (0,89-241)

4,350,23

Overall 95% CI

Studies

1

! ! - 2" ! + 2"

! ! - 2" ! + 2"




All - Sirius

Pache

Ravel


48

19,9

32,1

1,32(0,63-2,78)

1,40(0,45-4,35)

1,72(0,75-3,95)

1,47 (0,89-241)

4,350,23

Overall 95% CI

Studies

1

! ! - 2" ! + 2"

! ! - 2" ! + 2"

! ! - 2" ! + 2"




All - Sirius

Pache

Ravel


48

19,9

32,1

1,32(0,63-2,78)

1,40(0,45-4,35)

1,72(0,75-3,95)

1,47 (0,89-241)

4,350,23

Overall 95% CI

Studies

1

! ! - 2" ! + 2"

! ! - 2" ! + 2"

! ! - 2" ! + 2"

! ! - 2" ! + 2"



Thank You!

[email protected]


mailto:[email protected]

mailto:[email protected]

results

Documents

absolute risk

risk difference00

research center of pr

education research

clinical benefitsthe

clinical practicesuzana

nnhci ci cici ci ci

nnt postest prob rdrd