El estudio fue financiado por el Deutsche Forschungsgemeinschaft. Nos gustaría agradecer al PD Dr. Armin Schmidtke y al Dr. Werner Strik por su consejo y evaluación estadística de los datos. También nos gustaría agradecer al PD Dr. Gerd Jungkunz (Director del State Hospital Lohr/Main) y al Dr. Schottky (Director del State Hospital Werneck) por su atenta cooperación en la búsqueda de gemelos.

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