Research methods can help by deciphering the direction of the relationship , this helps greatly when looking at the cause
and effect relationship as it deciphers the direction of he relationship , this helps greatly when looking at the cause and effect relationship as it can easily tell the research what the effect is and the entity( entities) that may have caused it.
It can tell you if the cause and effect relationship is strong or weaker thus hinting at the strength of the correlation… the stronger th correlation the greater the effect for example one of the most highly contested and influential documents of it’s time was the Bell curve . The bell curve insinuates a positive and strong correlation between pale skinned individuals and intelligence and its attributes. http://academic.sun.ac.za/mathed/174/NatureNurture/Wikipedia.pdf
The cause and effect relationship is very useful when it comes to teasing out the medical roots of serious illnesses for example when it comes to the causes of cardiovascular disease due to individual differences it may be harder to tell the cause thus slowing down treatment and allowing such a potentially fateful disease to persist. http://www.ajcn.org/content/72/2/315.short
On the whole reseach methods use of the cause and effect relationship to decipher trends in data , as it is a very useful well developed tool in the psychology field.