The orthokeratology lens shifted the peripheral defocus to myopic by inducing an RCRPS. Previous study has reported that RCRPS could capture approximately 10% of the variance observed in ALG [
31], but this finding was based on ALGs in different isomyopic subjects, not in both eyes of subjects with anisometropia. For bilateral myopic anisometropes, here, we found that the RCRPS could capture around 7% of the variance observed in ALG whether in more myopic eyes or in less myopic eyes. Therefore, intersubject variables such as sex, age, genetic and environmental factors, and reading habits [
9,
12,
35,
36,
42‐
44], pupil size [
42,
45,
46], and corneal asymmetry [
3,
45], might account for the low proportion of variance explained. To address this, we applied a within-person interocular comparison to explore the dose-response between RCRPS and ALG. After controlling for the intersubject variables, linear regression revealed that the interocular difference in RCRPS could capture approximately 44.89% of the variance of the interocular difference in ALG. Interocular difference in RCRPS represents the difference in the front surface of the eye. However, at the back side, eyes started with different baseline ALs, which affect the ALG in myopic children treated with orthokeratology lenses [
44,
47]. Therefore, we added the interocular difference in baseline AL into the regression model, and the captured variance of interocular difference in ALG increased to 61.97%. The study by Xu et al. [
38] corroborate this point by demonstrating that the initial inter-eye AL difference was associated with the change of AL difference between two eyes of myopic anisometropia patients who used binocular orthokeratology lenses, but without mention the role of the induced RCRPS. This study is the first to propose that the interocular variation in RCRPS had a great influence on the rates of AL progress in two eyes, and subsequently contributes to the reduction of anisomyopia in children post-orthokeratology. The findings of Zhong et al.
22 and Hu et al.
24 appeared to support this view. They reported that the summed RCRPS achieved at early post-orthokeratology was negatively correlated with ALG. Moreover, it seemed that children with higher baseline SE were more liable to obtain greater areal summed RCRPS [
31]. And higher baseline SE of children or target power of orthokeratology lenses was closely correlated with the lower increase of ALG [
35,
48]. However, using multiple regression, we found that the contribution of the inter-eye difference in baseline SE on the interocular difference in ALG for myopic anisometropes wearing orthokeratology lenses was not statistically significant, indicating that there have been some situations illustrating substantially different initial myopia but comparable summed RCRPS. Additionally, after orthokeratology lens wear, treatment zone decentration is common and unavoidable [
49,
50]. Chen et al. proposed that different magnitudes of treatment zone decentration caused diversified changes in corneal refractive power [
51]. Previous study has found a positive correlation between the treatment zone decentration and the summed RCRPS after orthokeratology treatment [
33]. In this sense, the interocular variation in RCRPS of anisometropic children may be partly derived from differences in orthokeratology lens parameters that were used for each eye.