Researchers wanted to assess the effect of low alcohol consumption on reaction time in seniors, believing that even low levels of alcohol consumption can impair the ability to walk, thereby increasing the likelihood of falling. They identified 13 healthy seniors who were not heavy consumers of alcohol. The experiment took place in late afternoon. Each subject was instructed to have a light lunch and to not drink any caffeinated drinks in the 4 hours prior to arriving at the lab. The seniors were instructed to walk on a treadmill on which an obstacle would appear randomly. The reaction time was measured by determining the time it took the senior to lift his or her foot upon the appearance of the obstacle. First, each senior walked the treadmill after consuming a drink consisting of water mixed with orange juice with the scent and taste of vodka. The senior was then asked to drink two additional drinks (40% vodka mixed with orange juice). The senior then walked on the treadmill again. The average response time increased by 19 milliseconds after the alcohol treatment. The researchers concluded that response times are significantly delayed even for low levels of alcohol consumption.
A) What type of experimental design is this?
B) What is the response variable in this experiment? Is it quantitative or qualitative?
C) What is the treatment?
D) What factors were controlled and set at a fixed level in this experiment?
E) Can you think of any factors that may affect reaction to alcohol that were not cont rolled?
F) Why do you think the researchers used a drink that had the scent and taste of vodka to serve as the treatment for a baseline measure?
G) What was the conclusion of the study? To whom does this conclusion apply?

The matched pair experimental design was used here. In this type of design, the experimental units are paired up . Different individuals receive different treatments. A popular type of matched-pairs design is this; a response variable's effect on an experimental unit is measured before and after a treatment is applied.

Reaction time is the response variable here . It is quantitative because it can be counted or measured.

The treatment was water mixed with orange juice with the scent and taste of vodka and subsequently 40% vodka mixed with orange juice.

Food consumption and intake of caffeinated drinks were controlled and set at a fixed level in this experiment.

Age ,gender and weight may also affect the reaction of the seniors to alcohol .

This treatment served the purpose of a placebo thereby working as a control that helps us to establish a baseline treatment that can be used to compare with the results of other treatments .

The research conclusion is that response times are significantly delayed even for low levels of alcohol consumption in seniors .This conclusion can only be applied to healthy seniors that consume a low level of alcohol.