59 is not a tiny sample, they are being downvoted because they're demonstrating a lack of understanding of significance in statistics. The researchers conclude

59 is not a tiny sample, they are being downvoted because they're demonstrating a lack of understanding of significance in statistics. The researchers conclude "Mothers of children with ASD have many significantly different metabolite levels compared to mothers of typically developing children at 2–5 years after birth." And they back that conclusion up by describing their analytical process. If GP wants to dispute this conclusion, then the GP should explain why their method is flawed.