{
    "action": "final",
    "content": "Only two of the 16 analytical columns have missing values. The result above shows the full null profile.\n\n- **Academic_Performance_GPA**: 85 missing rows, or **1.89%** of the 4,500 rows.\n- **Perceived_Stress_Score**: 46 missing rows, or **1.02%**.\n\nThe other 14 columns checked have **0 nulls**. These include Student_ID, Age, Gender, Academic_Level, Primary_Platform, Daily_Usage_Hours, Weekend_Extra_Hours, Device_Type, Sleep_Duration_Hours, Sleep_Quality_Score, Late_Night_Usage, Social_Comparison_Frequency, Mental_Health_Index and Overall_Impact.\n\nThe missingness is low, so it is unlikely to distort overall results. It does touch two key outcome measures, GPA and stress. Averages of those two will be based on slightly fewer students than the full 4,500. The query covered the 16 data columns only, not the four ingestion-metadata columns (`_ingestion_timestamp`, `_batch_id`, `_source_file`, `_source_system`)."
}