COHN Exam AAOHN Prep Question And Answers
with Solutions 2024
1. Incident rate: # of newly occurring cases per person-time unit
2. Case studies (series): Identification or reporting of a group of cases; not a true
epi study
3. Cross sectional study: Survey to determine PREVALENCE of disease or expo-
sure at the same point in time; SELECTION BIAS IF ILL INDIV ARE GONE. Another
shortcoming is that it can only show association between exposure and disease: did
the disease precede exposure or vice versa? Health status of those who left work?
4. Amputation PPE: Recommended gloves mask eye protection
5. Work practice control definition: Reduce likelihood of exposure by altering the
manner in which a task is performed (not to be associated with engineering controls)
6. Compute range of sample distribution:
7. Cohort study (longitudinal or follow up study): Exposed and nonexposed
groups followed over time to determine who develops the disease; MOST direct eval
of health and disease patterns; MEASURES RISKS AND EXPENSIVE
8. Case control study: Comparison of exposure among individuals with disease
(cases) and others without disease (controls); retrospect or case referent eval done
to determine who was ir wasnt exposed; LESS EXPENSIVE AND RECALL BIAS
FOR THOSE EXPOSED
9. Environmental effects of heavy metal contaminants: Ex: Pb, Cd
Accumulate in subsoil
Toxic accumulation in veggies, fruits, pica activity, leaching into drinking water
10. Body burdens of Pb and Cd: Lead induced porphyria (skin and nervous
system), aplastic anemia (bone marrow toxicity) neuro (lowered IQ and attention
deficit)
11. Regulatory principles for limiting potential health threatening exposures-
: AGIH, OSHA: permissible work place exposures
DOT, EPA, OSHA and state agencies: enable statutes and regs to establish work-
places to be free of potentially hazardous exposures to toxic substances
12. OSHA PEL: Highest permissible level in 8hr work day
13. NIOSH TLV: Maximal avg encountered value that can be safely experienced in
8hr day; usually SAME OR LOWER THAN PEL
14. OSHA STEL: Max permissible exposure in a 15min time period (short term)
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, 15. NOEL (no observable effect level): Exposure level in humans not expected to
produce adverse effects; extrapolated safety factor of 10 from animal data
16. IDLH: Immediate danger to life or health
17. LOEL (lowest observable effect level): Lowest level of exposure capable of
producing a detectable effect
18. HBEL (health based exposure level): Exposure level pegged to conditions
necessary to ensure the maintenance of well-being
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10
with Solutions 2024
1. Incident rate: # of newly occurring cases per person-time unit
2. Case studies (series): Identification or reporting of a group of cases; not a true
epi study
3. Cross sectional study: Survey to determine PREVALENCE of disease or expo-
sure at the same point in time; SELECTION BIAS IF ILL INDIV ARE GONE. Another
shortcoming is that it can only show association between exposure and disease: did
the disease precede exposure or vice versa? Health status of those who left work?
4. Amputation PPE: Recommended gloves mask eye protection
5. Work practice control definition: Reduce likelihood of exposure by altering the
manner in which a task is performed (not to be associated with engineering controls)
6. Compute range of sample distribution:
7. Cohort study (longitudinal or follow up study): Exposed and nonexposed
groups followed over time to determine who develops the disease; MOST direct eval
of health and disease patterns; MEASURES RISKS AND EXPENSIVE
8. Case control study: Comparison of exposure among individuals with disease
(cases) and others without disease (controls); retrospect or case referent eval done
to determine who was ir wasnt exposed; LESS EXPENSIVE AND RECALL BIAS
FOR THOSE EXPOSED
9. Environmental effects of heavy metal contaminants: Ex: Pb, Cd
Accumulate in subsoil
Toxic accumulation in veggies, fruits, pica activity, leaching into drinking water
10. Body burdens of Pb and Cd: Lead induced porphyria (skin and nervous
system), aplastic anemia (bone marrow toxicity) neuro (lowered IQ and attention
deficit)
11. Regulatory principles for limiting potential health threatening exposures-
: AGIH, OSHA: permissible work place exposures
DOT, EPA, OSHA and state agencies: enable statutes and regs to establish work-
places to be free of potentially hazardous exposures to toxic substances
12. OSHA PEL: Highest permissible level in 8hr work day
13. NIOSH TLV: Maximal avg encountered value that can be safely experienced in
8hr day; usually SAME OR LOWER THAN PEL
14. OSHA STEL: Max permissible exposure in a 15min time period (short term)
1/
10
, 15. NOEL (no observable effect level): Exposure level in humans not expected to
produce adverse effects; extrapolated safety factor of 10 from animal data
16. IDLH: Immediate danger to life or health
17. LOEL (lowest observable effect level): Lowest level of exposure capable of
producing a detectable effect
18. HBEL (health based exposure level): Exposure level pegged to conditions
necessary to ensure the maintenance of well-being
2/
10
