“…Treatment outcome studies have found that assertiveness training improves general self-esteem, self-concept, and internal locus of control (Hammen et al, 1980;Meyer, 1991;Percell et al, 1974;Warren, 1977;Workman et al, 1986). Treatment outcome studies have found that assertiveness training improves general self-esteem, self-concept, and internal locus of control (Hammen et al, 1980;Meyer, 1991;Percell et al, 1974;Warren, 1977;Workman et al, 1986).…”