title: Advanced myopia, prevalence and incidence analysis.
abstract: OBJECTIVE
  Various high-percentage high-incidence medical conditions, acute or chronic, start at a particular age of onset t1 (years), accumulate or progress rapidly, with a system time constant t0 (years), typically from 1 week to 5 years, and then level off at a plateau level [Formula: see text], ultimately affecting 10-95% of the population. This report investigates the prevalence and incidence functions for myopia and high myopia as a function of age.
  
  
  METHODS
  Fundamental prevalence versus time and incidence versus time results allow continuous prediction of myopia and high myopia population fractions as a function of age. This is a retrospective study. Nine reports are calculated with N = 444,600 subjects. There were no interventions other than usual regular eye examinations and subsequent indicated refraction change.
  
  
  RESULTS
  The main result is continuous prediction of myopia prevalence-time data along with incidence rate data (%/year), age of onset (years), system plateau level, and system time constant (years). These parameters apply to progressive myopia and high myopia (R < -6 D), useful over several decades.
  
  
  CONCLUSIONS
  The primary finding of this research is that the prevalence ratio of high myopes (R < -6.0 D) to common myopes is expected to increase from 15% entering college to 45% or more after college and graduate school. These statistics are particularly relevant to the many years of study required by M.D., Ph.D., and M.D./Ph.D. programs.
authors.affiliation: Department of Bioengineering, BGKT Consulting Ltd, Huntington, NY, 11743, USA. prgreenBGKT@gmail.com.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Greene
authors.affiliation: BGKT Computer Sciences, Huntington, NY, USA.
authors.forename: Judith M
authors.initials: JM
authors.lastname: Greene
mesh_terms: D017677:Age Distribution; D004522:Educational Status; D006801:Humans; D015994:Incidence; D009216:Myopia / Q000453:epidemiology*; D047728:Myopia, Degenerative / Q000453:epidemiology; D015995:Prevalence; D012044:Regression Analysis; D012189:Retrospective Studies
keywords: Exponential equations; High myopia; Incidence; Myopia; Onset age; Plateau level; Prevalence; Reading glasses; Time constant