To what extent has shared equity homeownership been evaluated?

There has been some data collection, but no rigorous evaluation.  The most comprehensive data collection was done by John Davis evaluating the Burlington Community Land Trust.  The Burlington study looked at 259 moderately-priced units that were developed between 1984 and 2002 and 97 resales that occurred between 1988 and 2002. The study found that individuals modestly increased their wealth and that affordability was preserved.  Of the 97 resales tracked, 60 of the residents made the leap to market rate homeownership when they left the BCLT.