B
Bias in epidemiological studies 155
Biological plausibility of the association 29
Blonde hair and blue eyes 19
C
Case control study 138
advantages 157
easy of conduct 157
faster results 157
inexpensive due 157
more than one RFs 157
no attrition 157
no ethical problems 158
data analysis 151
determining exposure levels 151
disadvantages 158
information on exposure 147
sources of information on exposure status 148
matching 144
group matching 147
paired matching 147
selection of controls 147
selection of cases 140
sources of cases 141
sources of controls 142
Causative association 24
Chance variation 14
Cohort studies 161
advantages 179
disadvantages 180
steps 166
data analysis 173
getting data on exposure to risk factor 168
identification of exposure cohort 166
regular follow-up 171
selection of control 169
types 163
combination of retrospective and prospective cohort design 165
concurrent 163
non-concurrent 163
prospective cohort design 165
Community trial 223
Concurrence by chance 18
Consistency of association 28
Coronary heart disease 10
D
Design of a randomized clinical trial 217
Design of a randomized controlled trial 233
steps 233
choosing the reference population 233
choosing the study or experimental population 233
data analysis to determine the effect 234
fullow-up 233
intervention to the members of treatment groups 233
random allocation to study and control group 233
Differences between case control and cohort study 183
E
Epidemic curve 118
Epidemiological studies 87
experimental studies 92
observational studies 89
analytical studies 90
descriptive study 89
usual sequence 93
AIDS 93
aims 5
causation of disease 6
community diagnosis 5
data for 7
evaluation 7
implementation 7
planning 7
Evaluation 305
Exposed cohort 186
M
Male sex and hemophilia 19
Measuring disease frequency 47
Monitoring 298
air quality 298
functioning of a health facility 299
health program 298
intrauterine growth monitoring 298
nutritional status 299
water quality monitoring 298
Mortality rates 58
case fatality rate 66
crude death rate 58
group specific death rates 64
age and sex specific death rates 65
infant mortality rate 64
neonatal mortality rate 64
proportional mortality rate 67
cause 69
specific death rates 62
use of cause 63
standardised rates 71
indirect standardization 72
survival rate 70
P
P value 15
Paired ‘t’ test 255
Person distribution 109
Phases of vaccine trial 224
Place distribution 108
Population-attributable risk 176
S
Secondary attack rate 50
Significance of incidence and prevalence 53
Smoking and lung carcinoma 20
Sources of bias 156
case control studies 156
Berkesonian bias 156
bias due to a confounding factor 156
bias in obtaining information 156
recall bias 156
selection bias 156
experimental studies 220
evaluation bias 220
observer bias 220
subject variation 220
Standard error of difference 240
Standardization 265
direct 265
indirect 266
community diagnosis 279
determining risk to individual 281
evaluation of new therapy 281
filling in the gaps in the natural history of a disease 282
identification of syndromes 282
planning and evaluation 280
searching for the causes of a disease 282
Strength of association 26