A laboratory science student is making blood films that are too long and thin. What change in technique would most likely improve the films?

When making blood films, the technique and angles used can significantly influence the final appearance of the slide. In this situation, the blood films are described as too long and thin, which indicates that the film is being spread too far, resulting in an inadequate thickness and an elongated shape.

Increasing the acute angle of the pusher slide is the most effective change to rectify this issue. By adjusting the angle, the momentum of the blood spread is altered, allowing for a thicker film to be created. A greater angle allows the pusher slide to make better contact with the drop of blood in a way that spreads the blood evenly and more effectively, which can lead to a shorter and thicker film. This modification addresses the problem directly by altering how the blood is spread across the slide.

Other techniques such as changing downward pressure or the position of the drop of blood may also have an effect, but in this case, modifying the angle of the pusher slide has a more direct impact on achieving the desired film characteristics of thickness and proper length.