diff --git a/src/index.js b/src/index.js
index 5de1497..9ab8340 100644
--- a/src/index.js
+++ b/src/index.js
@@ -83,7 +83,7 @@ export class HasScopeDirective extends SchemaDirectiveVisitor {
           decoded["scope"] ||
           [];
 
-      if (expectedScopes.some(scope => scopes.indexOf(scope) !== -1)) {
+      if (expectedScopes.some(scope => scopes.includes(scope))) {
         return next(result, args, { ...context, user: decoded }, info);
       }
 
@@ -113,7 +113,7 @@ export class HasScopeDirective extends SchemaDirectiveVisitor {
             decoded["scope"] ||
             [];
 
-        if (expectedScopes.some(role => scopes.indexOf(role) !== -1)) {
+        if (expectedScopes.some(role => scopes.includes(role))) {
           return next(result, args, { ...context, user: decoded }, info);
         }
         throw new AuthorizationError({
@@ -153,7 +153,7 @@ export class HasRoleDirective extends SchemaDirectiveVisitor {
           decoded["role"] ||
           [];
 
-      if (expectedRoles.some(role => roles.indexOf(role) !== -1)) {
+      if (expectedRoles.some(role => roles.includes(role))) {
         return next(result, args, { ...context, user: decoded }, info);
       }
 
@@ -181,7 +181,7 @@ export class HasRoleDirective extends SchemaDirectiveVisitor {
             decoded["role"] ||
             [];
 
-        if (expectedRoles.some(role => roles.indexOf(role) !== -1)) {
+        if (expectedRoles.some(role => roles.includes(role))) {
           return next(result, args, { ...context, user: decoded }, info);
         }
         throw new AuthorizationError({