diff --git a/src/client/pages/YieldStudyDashboard.tsx b/src/client/pages/YieldStudyDashboard.tsx
index ac97104..63158aa 100644
--- a/src/client/pages/YieldStudyDashboard.tsx
+++ b/src/client/pages/YieldStudyDashboard.tsx
@@ -108,11 +108,11 @@ export const YieldStudyDashboard: React.FC = () => {
             ]);
 
             // Normalizar estudos para garantir que as categorias tenham o campo 'id'
-            const normalizedStudies = (studiesRes.data || []).map((s: YieldStudy) => ({
+            const normalizedStudies: YieldStudy[] = (studiesRes.data || []).map((s: YieldStudy) => ({
                 ...s,
-                categories: (s.categories || []).map(cat => ({
+                categories: (s.categories || []).map((cat): PieceCategory => ({
                     ...cat,
-                    id: cat.id || (cat as { _id?: string })._id // Garante ID único
+                    id: (cat.id || (cat as { _id?: string })._id) as string // Garante ID único
                 }))
             }));
 
@@ -156,11 +156,11 @@ export const YieldStudyDashboard: React.FC = () => {
 
         try {
             const res = await yieldStudyService.createStudy(newStudy);
-            const normalized = {
+            const normalized: YieldStudy = {
                 ...res.data,
-                categories: res.data.categories.map((cat: PieceCategory & { _id?: string }) => ({
+                categories: res.data.categories.map((cat: PieceCategory & { _id?: string }): PieceCategory => ({
                     ...cat,
-                    id: cat.id || cat._id
+                    id: (cat.id || cat._id) as string
                 }))
             };
             setStudies([normalized, ...studies]);
@@ -226,7 +226,7 @@ export const YieldStudyDashboard: React.FC = () => {
 
         // 1. Aplica a atualização na categoria específica
         const newCategories = selectedStudy.categories.map(c => {
-            const currentId = c.id || (c as { _id?: string })._id;
+            const currentId = (c.id || (c as { _id?: string })._id) as string;
             return currentId === id ? { ...c, ...updates } : c;
         });
 
@@ -428,11 +428,11 @@ export const YieldStudyDashboard: React.FC = () => {
                                 <div className="absolute -inset-1 bg-gradient-to-br from-primary/20 via-transparent to-blue-500/10 rounded-[32px] blur-xl opacity-0 group-hover:opacity-100 transition-all duration-700"></div>
                                 <Card
                                     onClick={() => {
-                                        const normalized = {
+                                        const normalized: YieldStudy = {
                                             ...study,
-                                            categories: study.categories.map(cat => ({
+                                            categories: study.categories.map((cat): PieceCategory => ({
                                                 ...cat,
-                                                id: cat.id || (cat as { _id?: string })._id
+                                                id: (cat.id || (cat as { _id?: string })._id) as string
                                             }))
                                         };
                                         setSelectedStudy(normalized);