TI - INdex to advertisers PT - JOUR DP - 1989 TA - JAMA pages = {1898}, VI - 262 IP - 13 AID - 10.1001/jama.1989.03430130176060 [doi] 4100 - http://dx.doi.org/10.1001/jama.1989.03430130176060 SO - JAMA October 6, 1989 262(13):1898