Theoretically, it is considered low myopia/nearsightedness and it is not a problem, you do not need to put much emphasis on it. Unless cycloplegic eyedrops were used, this number may actually be lower; i.e., he may be even less nearsighted than -1.50. An ophthalmologist (Eye MD) would ordinarily use this technique in a child of this age. He should be rechecked annually to be certain that the prescription remains stable. However, small changes (progression) are normal as he is growing. High myopia (greater than six diopters) carries a higher risk of retinal detachment (when the retina peels away from the back of the eye).