I had trouble understanding the standard deviations in the study so had chatgpt translate them into terms I could understand.

FYI:

1. General Psychopathology Factor (g-factor):

   • The “602-million General Psychopathology factor points” refers to the cumulative impact of leaded gasoline exposure across the U.S. population on a mental health risk measure.
   • A 0.13 standard deviation increase means that, on average, the population’s liability to mental illness shifted slightly higher. While it’s hard to translate standard deviations into percentages directly, a 0.13 SD is considered a small effect, equivalent to about a 5.2% increase in risk when interpreted broadly.

2. 151 Million Excess Mental Disorders:

   • This means that, due to lead exposure, there were 151 million additional cases of mental disorders in the U.S. population over time. This doesn’t mean 151 million people, as some individuals might have more than one disorder.

3. Internalizing Symptoms:

   • Internalizing symptoms (like anxiety and depression) showed a 0.64 standard deviation increase. This is a medium-to-large effect size and can be roughly understood as a 24% increase in these symptoms across the population.

4. AD/HD Symptoms:

   • Attention-Deficit/Hyperactivity Disorder symptoms increased by 0.42 standard deviations, which is a moderate effect size. This corresponds to about a 16.5% increase in population-level AD/HD symptoms.

5. Personality Traits (Neuroticism and Conscientiousness):

   • Neuroticism (tendency to experience negative emotions) increased by 0.14 standard deviations (a small effect, about a 5.6% increase).
   • Conscientiousness (self-discipline and organization) decreased by 0.20 standard deviations, which is a slightly larger small effect, about an 8% decrease.