Correlations? Yes. Causations? No.
War and economy are different metrics. Both world economic crisis and world wars are huge historical events with multiple, far-reaching causes. Is there then a direct path, from a general crisis to a world-wide war? Well, no.
Put simply, since war and economy do not work at the same "plane", you can have a huge, broad, deadly war and still have huge economic growth, like in colonial America, or in Afghanistan, or in Persia prior to Alexander's conquests. Afghanistan has been a country on permanent civil war since the '80 has economically grown consistently, at a fast pace. This principle works from local wars to worldwide wars.
Also, a single "causation" to large scale events, like world wars, cannot be ascertained. Even when an economic crisis sets the stage for a large conflict, you cannot rule out the technological advances, diplomacy, or any other factor that leaders leveraged to actually decide to go to war (aka: true, direct causes).
Many examples in the timelines I build for HistoryTimeline.com have given me the idea that that wars and economy are obviously related, but that they really have different natures, and can be quite unnafected. Many, many times war is brought by economic growth. Just some examples: Nigeria after decolonization (oil prosperity), the conquest of Old Kingdom of Egypt, also the Islamic conquests.The Islamic conquests, truly a world war of their time, are a good example. They targeted prosperous areas so they could tax them.