About
Hello! I'm Theodoros, and I'm on my journey to becoming a data analyst. I'm currently developing my skills in SQL, Tableau, and Excel, and building this portfolio to showcase how I turn data into clear, actionable insights. I'm excited by the endless possibilities data offers — especially when it comes to solving real-world problems and shaping smart decisions.
Operations & Data Coordinator
Background
I’ve worked in healthcare, insurance, and sports event operations — always using data to improve how things run. From managing patient and financial info in diagnostic centers, to analyzing sales and client data in insurance, to optimizing stadium food and drink sales, I’ve learned how to turn numbers into smarter decisions. These experiences help me bring a practical, results-focused mindset to data analysis
- Birthday: 11 December 1982
- City: Trikala, Greece
- Degree: BSc in Geology
- Age: 43
- Email: tmalezidis@gmail.com
- Freelance: Not Available
Skills
I'm actively building my skills in SQL, data visualization, and spreadsheet work— here's a look at the tools I'm working with:
Database & Data Management
Programming & Query Languages
Data Visualization
Spreadsheet & Analysis
Experience
While I haven’t officially held the title of Data Analyst, I’ve consistently worked with data throughout my career — often by taking initiative beyond my formal responsibilities. Early on, I recognized how valuable accurate data and thoughtful analysis can be for improving performance and driving smarter decisions. That realization led me to deepen my skills and explore ways to turn data into real business value .
Professional Experience
Operations & Data Coordinator
Diagnostic Imaging Center
2022 – Today
Trikala, Greece
- Designed and maintained a PostgreSQL database to centralize and analyze referral, patient, and financial data from RIS and other sources
- Analyzed revenue, profit, appointment volume, exam types, and referral sources using Excel and SQL; presented insights to stakeholders through Tableau dashboards and KPIs, enabling data-driven decisions that improved operational efficiency and contributed to 18% revenue growth
- Used SQL analysis to optimize team workload and shift planning, enabling a 15% increase in daily appointment capacity without additional resources
Medical Data Coordinator & Operations Analyst
Diagnostic Imaging Center
2017 – 2022
Thessaloniki, Greece
- Managed and maintained the internal RIS database, registering patient records and tracking examination history (MRI, CT, ultrasound, blood tests, checkups)
- Monitored staff performance and proposed workflow optimizations that improved operational efficiency
- Analyzed referral patterns from external physicians and supported targeted outreach efforts, helping the marketing team increase engagement with high-referral doctors and drive patient volume growth
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Insurance Advisor
Health & Life Insurance Firm
2012 – 2017
Thessaloniki, Greece
- Maintained and analyzed a personal and shared client portfolio, using Excel to monitor sales performance and client retention trends
- Built Excel dashboards to track individual and team commission data, enabling transparent performance comparisons and effective goal-setting
- Conducted sales analysis to identify high-value clients — insights led to a cross-selling lift from 1.5 to 2.2 products per client
- Analyzed provider-level profitability data to identify high-commission products; presented findings to my team to support targeted marketing — contributed to a 12% average QoQ commission growth over five consecutive quarters
F&B Operations Coordinator (Stadium-Owned Concessions)
Stadium Operations – Professional Football Club
2007 – 2011
Thessaloniki, Greece
- Performed zone-level sales analysis by correlate fan attendance data to transaction volumes using Excel, and present insights used to reallocate staff more efficiently, leading to, in some cases, a 20% increase in revenue in targeted areas
- Built and delivered monthly and quarterly reports to management using Excel dashboards and pivot tables, highlighting revenue, units sold, and profit margins per item — enabled data-driven decisions on product promotions and inventory strategies based on demand and profitability
- Used foot traffic and sales data to guide staff deployment across service zones, reducing excess staffing in low-demand areas and improving profit margins through better labor cost control
Portfolio
Below are selected projects that showcase my work. Each includes a brief description and a direct link — feel free to dive into the details!
- All
- Data Analysis
- Data Engineering
- Data Visualization
