Yes. It's pretty well-established that the earlier it starts, the worse it's
going to get.

The rule of thumb is all we have to go on. It predicts that she won't change
much more.

-MT, OD

If you get bored, you can quickly skim the following article:

http://www.nap.edu/openbook.php?isbn=0309040817&page=23

It's the product of meta-studies (studies OF studies) regarding myopic
progression, and includes much information about "age of onset"
effect.

But there seems to be a decided genetic component, so ... making
assumptions based on the average could be a lousy approach.

Since she's a low myope, I'd suggest that she wear her glasses only
when needed to produce sharp vision, and that you look into "visual
hygiene," ensuring that she is meticulous about this.

Also, though it sounds prosaic: good diet, fresh air, sunshine,
outdoor activities ... all likely help.

Neil
NOT a doctor

ps: may as well get this in now: there's an "Otis Brown" who trolls
this site.  You'd do well to ignore him.  As most will tell you, he's
woefully uninformed.  As many will tell you, his advice has hurt
people.

Correlation studies have been  done, you can search for them on PubMed
at

http://www.ncbi.nlm.nih.gov/sites/entrez?db=PubMed

in the search field put  "17896302"  and when the study comes up,
click on "see all related links".  Bear in mind that these are
population studies, you can say from them that for a group of people
of XX age at first myopia, YY% of  them will get to -Z.ZZD of myopia
by age XX,  but you cannot use the studies to predict what will happen
to any one particular person.

You daughter is mildly myopic and developed it at an older age, she
will likely not progress very much more; however she is already
outside the "rule of thumb" guides, in starting myopia after age 18 so
the usual statements may not be at all predictive in her case.

The study referenced above:

Factors associated with high myopia after 7 years of follow-up in the
Correction of Myopia Evaluation Trial (COMET) Cohort.Gwiazda J, Hyman
L, Dong LM, Everett D, Norton T, Kurtz D, Manny R, Marsh-Tootle W,
Scheiman M; Comet Group.
New England College of Optometry, Boston, Massachusetts 02115, USA.
gwiazdaj@neco.edu

PURPOSE: To evaluate factors associated with the development of high
myopia (worse than -6.00 D) over 7 years of follow-up in the COMET
cohort. METHODS: COMET enrolled 469 ethnically diverse children (6-11
years) with myopia between -1.25 and -4.50 D. They were randomized to
either progressive addition lenses (PALs) or single vision lenses
(SVLs), and followed for 5 years in their original lens assignment and
2 additional years wearing either spectacles (PALs or SVLs) or contact
lenses. Refractive error was measured annually by cycloplegic
autorefraction and axial length by A-Scan ultrasonography. Myopia for
each child was defined as the mean spherical equivalent refractive
error (SER) of the 2 eyes. Analyses were based on 7 years of follow-
up. Time to high myopia was analyzed by Cox proportional hazard models
and linear regression. Parental refraction data were available from
240 COMET subjects. RESULTS: Younger (6-7 years) versus older (11
years) age at baseline was a significant risk factor (adjusted hazard
ratio (HR) = 6.6, 95% CI = 3.4, 12.7) for having high myopia within 7
years. More (SER from -2.26 to -4.50 D) vs. less (SER from -1.25 to
-2.25 D) baseline myopia was also a significant risk factor for high
myopia at 7 years (adjusted HR = 7.4, 95% CI = 4.4, 12.4). Gender,
ethnicity, and treatment assignment were not associated with the risk
of high myopia within 7 years. Increased number of myopic parents was
associated with a significant risk of high myopia in the children (p =
0.008). CONCLUSIONS: Children who developed high myopia during 7 years
of follow-up were younger and had more myopia at baseline. They also
were more likely to have two myopic parents. These children may be at
greater risk for sight-threatening conditions later in life.

PMID: 17896302 [PubMed - indexed for MEDLINE]