Exhibit 11.1 Renal Treatment Centers, Inc. and Subsidiaries COMPUTATION OF NET INCOME PER COMMON SHARE AND NET INCOME PER COMMON SHARE--ASSUMING DILUTION for the quarter ended March 31, 1997 and 1996 Three Months Ended March 31, 1997 1996 ---------------------------- Reconciliation of numerator: Net income for use in computing net income per common share $ 3,963,116 $ 1,458,597 Add back interest on note, tax effected 34,122 67,665 ---------------------------- Adjusted net income for use in computing net income per common share--assuming dilution $ 3,997,238 $ 1,526,262 ============================ Reconciliation of denominator Weighted average number of shares outstanding for use in computing net income per common share 24,509,763 24,036,542 Weighted average shares assumed issued upon conversion of note 441,191 661,501 Dilutive effect of outstanding stock options 751,657 766,102 ---------------------------- Weighted average number of common shares and equivalents outstanding--assuming dilution 25,702,611 25,464,145 ============================ Net income per common share $ 0.15 $ 0.06 ============================ Net income per common share--assuming dilution $ 0.15 $ 0.06 ============================