COMSAE level 2 111
Prevalence - number of cases at a partic-
ular time
Incidence - number of new cases
prevalence vs incidence
odds ratio: for case control studies con-
trol for disease and examine exposure
odds dz+ in exposed group/odds dz+ in
unexposed
(a/b)/(c/d)
ratio is not a fraction! so the bottom num-
ber is not the total its the unaffected
relative risk: for cohort studies that con-
trol for exposures and examine who got
odds ratio vs relative risk the disease
prob getting dz exposed/prob getting dz
unexposed
a/(a+b) / c/(c+d)
case-control studies
When is an odds ratio used
, COMSAE level 2 111
When is a relative risk ratio used? RCT or Cohort study
Absence of secondary sexual character-
istics by age 13
failure of menarche by 16
Delayed puberty in girls
no testicular growth has occurred by age
14 or no skeletal growth spurt has oc-
curred by age 18
delayed puberty in males
MCC of growth delay. growth lags behind
others in same age but remains consis-
tent. Often there is family history
Will have delayed bone age
constitutional growth delay
tubular casts with foreign body giant cell
reaction
light chains are toxic to the renal tubular
epithelium
occurs in MM
Prevalence - number of cases at a partic-
ular time
Incidence - number of new cases
prevalence vs incidence
odds ratio: for case control studies con-
trol for disease and examine exposure
odds dz+ in exposed group/odds dz+ in
unexposed
(a/b)/(c/d)
ratio is not a fraction! so the bottom num-
ber is not the total its the unaffected
relative risk: for cohort studies that con-
trol for exposures and examine who got
odds ratio vs relative risk the disease
prob getting dz exposed/prob getting dz
unexposed
a/(a+b) / c/(c+d)
case-control studies
When is an odds ratio used
, COMSAE level 2 111
When is a relative risk ratio used? RCT or Cohort study
Absence of secondary sexual character-
istics by age 13
failure of menarche by 16
Delayed puberty in girls
no testicular growth has occurred by age
14 or no skeletal growth spurt has oc-
curred by age 18
delayed puberty in males
MCC of growth delay. growth lags behind
others in same age but remains consis-
tent. Often there is family history
Will have delayed bone age
constitutional growth delay
tubular casts with foreign body giant cell
reaction
light chains are toxic to the renal tubular
epithelium
occurs in MM
