Joint strength is largely determined by the holding power of the dowels. The longer the dowel, the greater the strength. The thicker the panel, the stronger the joint. Biscuits have equivalent strength, but are easier to align at assembly. Dados are better, but less attractive.
Dovetails are excellent, but require precise and time-consuming machining.
Metal Fasteners for PB and MDF Abstract Screws, nails, and staples are widely used. Screws are strongest. Screw diameter affects strength little, but screw length directly affects it. High internal bond strength PB holds screws better. Edge screws have half the strength of face screws.