Final answer:
The statement about the correlation between early intervention and prognosis is true, with studies confirming better outcomes with earlier interventions. Positive and negative correlations simply describe the relationship between variables, not health benefits. Scientific evidence is crucial in assessing the effectiveness of treatment methods.
Step-by-step explanation:
The statement 'There is a correlation between the time a child begins intervention and their prognosis' is true. Early intervention in developmental delays or disorders typically leads to better outcomes. This is because early intervention allows for the possibility of capitalizing on the brain's plasticity during its prime developmental stages. An example is the intensive behavioural treatment for children with autism, where studies, such as the one by Sallows and Graupner (2005), have noted favourable long-term effects when intervention started at a younger age.
It is important to clarify that a positive correlation does not necessarily mean there are health benefits - it simply means that as one variable increases, so does the other. Conversely, a negative correlation indicates that as one variable increases, the other decreases.
Consequently, the statement that the risk of having a child with Down syndrome is primarily associated with maternal age rather than lifestyle is accurate. As maternal age increases, the risk of having a child with Down syndrome increases as well.
When addressing the issue of whether a treatment method is effective, we should rely on evidence from scientific studies. For instance, if evidence suggests that a method reduces the proportion of patients who develop a disease, it can be considered effective. This is validated through well-designed research studies and statistical analysis that provides sufficient evidence.