This is important to see which side of the inside market is being transacted against, either the best bid or best ask. Once you can determine that, you must see how the market makers are positioning themselves in response to those transactions.

If the majority of transactions are going off at the best bid and market makers are not refreshing their quotes at that level (which will be indicated by a shrinking number of market makers on the inside bid), the price is headed down. If the transactions are against the best bid, but the market makers are refreshing their prices, or more market makers are joining the best bid, then there is real support at that level and an uptick can be expected.

A comparable situation is true if transactions are going off at the best ask. This means that traders have an appetite for that security. If the market makers try to get out of their way by reducing their numbers on the best ask, you can bet the stock is going up. If the market makers stay and refresh their prices, you can say the buying pressure will likely subside and the price will fall.

The analysis you should perform is not just to look at it at any one point in time and see that there are more market makers on one side than the other. It is the flow and how the market makers react to transactions that gives you information.